AudioCircle
Other Stuff => Archived Manufacturer Circles => Aspen Amplifiers => Topic started by: stvnharr on 16 Mar 2007, 03:00 am
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Hello All,
I have finished with the cap modifications to the GK-1, as new output caps arrived this week and were quickly installed. I have now christened my GK-1 as GK-1 Platinum, as the Sonic Platinum caps have brought the GK-1 to new heights of audio performance.
The C-1 input Platinum cap has been in the preamp now for just over a month. The sound as reported in my earlier post is much the same, although it does seem as if things have opened up a bit lately to a much broader and wider sound presentation. Every little musical detail seems to be easily heard, with tinkly little things twinkling quickly, whacks being soundly quickly whacked, and notes lingering into long decays.
The new output coupling caps are 1 uf Mundorf Silver/Oils. I had been thinking of 250V VH-OIMP’s as their size was easily accommodated on the board, but in the end I went with the Mundorf’s. They are nearly as large as the Platinum’s, but not as heavy. I was able to fit them on the board, barely.
These caps have made an immediate and noticeable difference in the sound, adding a nice refinement to the pre-existing sound that I heard with the Auricaps in this position.
In summation, the modifications are as follows:
C-1 input cap to SS gain stage – Sonic Cap Platinum 1 uf
C-19 input cap to tube grid - Sonic Cap Platinum .01uf
C-21 output coupling cap - Mundorf Silver/Oil 1 uf
The teflon caps are the single most definable improvement I have ever made to an audio system, more so than even a total unit replacement. This is not just a simple cap modification; it is a total unit sound upgrade of immense proportions. The playback sound of the audio system is taken to a totally new level with these caps.
There also is not cheap way to accomplish this. The 1uf Platinums are $100 ea. and the VH-Audio TFTF’s are 30% more. One may be tempted to just get a small bypass cap as a cheap option. I just don’t think bypassing a signal path cap works. I’ve tried this in the GK-1 and Aksa N+ output couplers and heard absolutely no difference in sound. You need to use the full value cap in the C-1 input cap position!
You have to think of this as a total audio system upgrade rather than a cap change. Thus, the cost of the caps is really a bargain with the sound that results.
Hugh has heard the sound of this modification in my system himself, just a few days ago. Unfortunately the new output caps had not yet arrived, but they are more like icing on the cake. He’s heard the improvement the Platinum teflons make to the sound. You can contact him direct for his personal opinions, impressions, and thoughts.
Finally, if you have a GK-1 and want to take it to the ultimate level of sound reproduction, the teflon cap modification is a MUST. You cannot do anything else to the unit, or your system really, with as much impact as this modification!
Steve
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Thanks Steven, your observations and comments much appreciated.
The addition of Platinum Sonicaps, made with teflon dielectric, takes the GK1 to the pinnacle of transparency. I have heard nothing better with the Lifeforce power amplifier, but then audio memory is so poor that one really needs AB testing to be definitive. But there is no doubt that if that was good, with the Mundorf on the output coupler the sound would be absolutely the last word in natural, dynamic and resolving sound.
However, one must be circumspect. The cost of these caps, up around $US100 for the Sonicaps and not much less for the Mundorf Supreme silver/oils, adds a cool $US350 to the price of admission. For a kit, this is fantasy land, but for many audiophiles it's short term pain driven by the infamous, compulsive 'need to tweak'. I appreciate the opportunity Steven gave me to hear this, I would not by myself have done the mod for purely economic reasons, but here's how I feel......
I will eventully redesign the SS section of the Swift, the non-kit, fully built Aspen preamp, to exploit the teflon caps. I have spent many long hours musing on circuit configurations and ways of reconfiguring the input stage to use much smaller caps, so as to minimise the cost of any teflons I use. This could take a LONG time!!
But I won't be releasing teflon caps for the kits, that is for certain!!
Thanks again, Steve!
Cheers,
Hugh
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The total cost of the caps I installed is around 300 USD plus shipping. This seems a lot for caps, but it's not much for what you get in return.
If you forgo things like NOS tubes, replacing electro caps on the SS stage, and a fancy attenuator, you can get the caps and maybe have money left over.
I realize there aren't many GK-1's out there, and many, if not most, already have numerous modifications. Do the caps, or at least the C-1 cap. You will be very pleased!
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Steve, Thanks for sharing. .....MUST resist ....MUST resist ....MUST resist :drool:
What did you settle on at C2?
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Darren,
I think C2 is the .47uf BG that Hugh gave me last year.
Don't resist!!!!
Steve
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thanks steve
I was planning on re-reading all the old posts to see what the final word was- probably still will, I appreciate the Cliff Notes version (and for all those not in the US or out of school for some time- Cliff Notes are the popular series of pocket books which summarize important intellectual works. Think of it like an academic "for Dummies series" please note that I am not knocking them, they can provide a good introduction but should not replace the original). now just need to find time to build it :|
jim
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Darren,
I think C2 is the .47uf BG that Hugh gave me last year.
Don't resist!!!!
Steve
I think the original C2 was a 10uF/16vw tantalum cap. PSP uses a 33uF BG NP, while AndyR uses a 22uF BG NX. Any reason you went with .47uF or was it just availability?
Fight.....ing ....temp.....tation ....must .....be.....strong. :lol:
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I don't have the large value Teflon caps (too expensive), but here's what I have done:
C1 = 2.7uF Mundorf ZN Polypropylene film & foil bypassed with 22nF Relcap TFT
C19 = 22nF Relcap TFT (increased value at Hugh's suggestion)
C21 = 4.7uF Mundorf ZN Polypropylene film & foil bypassed with 33nF Relcap TFT
As noted, Hugh suggested increasing C19 to 22nF if I was inserting a Teflon cap, and the C1 and C21 values were increased to maximise bass performance. With the stock 1uF value for C21, the f3 into the Orion crossover was around 16Hz, it is now about 3.5Hz.
C19 and C21 have just been changed, and I can't really give full comments on the sound quality as I haven't had the time to listen for much more than a couple of hours yet. However, there is a degree of bass power and openness that was never there before. I guess that things will open up further, but I am also hearing improvements similar to those Steven has commented on. The more powerful bass (to be expected) and an increased purity are pretty obvious.
I will post more comments when I have had a chance to listen further and get some run-in on the caps.
Cheers
Mike
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After reading all the threads on upgrading the GK-1 (and getting somewhat confused about what to do), it's very relieving reading this thread that you guys come up with :D
There seems to be widespread consensus that the teflon caps are the caps to use for C1 and C19, but I'm wondering if a teflon cap would not also be the ultimate cap for the C21? Comments, anyone?
My first inclinination was to go with a Mundorf Silver/Oil at C21 (like Steve), as I have very good experiences with these, but if a teflon cap would be even better, then why not? (and caps could be ordered from one source :wink: )
Did anyone experience any downside with using a teflon cap at C21?
At any rate, in my case the value of this cap would be around .033 uF, as I will use this cap to roll off the midrange, which is driven from the tube output, so the cap won't be too big and expensive. In conjunction with the midrange driver's own acoustic rolloff the cap rolloff introduced in this manner should give a very nice, sharpish rolloff. I used this type of rolloff in my previous preamp where it worked beautifully.
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Hi Jens,
I used the Mundorf cap for the output cap for 2 reasons:
1. Size, the 1uf Platinum is too big for the board here as there is not enough room underneath for it, so would have to mount off board and use flying leads
2. Cost/value of diminishing returns. The C1 Platinum opened up so much and the sound was so good even with the Auricap that I thought the large cost for the Platinum would not bring the same benefits as at the input. The Mundorf, while not exactly cheap at 38 USD seemed the most reasonable choice, especially as they are Jeff Glowacky's favorite cap after the Platinum's.
Jens, if you are going to use a .33uf teflon cap there should be no size issues on the board. Teflons I think are most certainly the choice for signal path caps if they fit and the money is okay.
Steve
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Hi Steve,
Thank you for your input on the output cap :wink:
Size is certainly an issue, as there aren't unlimited amounts of space on the GK-1 board, and there's certainly a huge difference in price on the 1 uFs, so I understand your choice.
Not so when you go for .033 or .047 uF. Mundorf and Sonicap prices and sizes are almost identical for those values - looks like I'm in a bit of luck there :green:
Guess I'll smash my piggy bank and see if it contains the 275 USD that these caps will set me back :lol:
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Hi Jens,
You should find that the teflon caps, especially the big C-1 cap will be a transformation. It sure was for me.
Steve
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Hi Steve,
I'm certain it will be. People in here tend to have good ears :wink:
Most likely, I'll be ordering the caps today!
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Oooooooooooooooohhhhhhhhhh,
You guys will all have better GK1s than I've got!! :drool: :drool: :drool: :drool:
:nono: Hugh
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Well, Hugh - you could update your own GK-1 along the same lines ..... :green:
But why not look at it i another way - you've got a whole bunch of people here who love your products so much that they feel they have to bring them to the sublime. I that was me, I would be very proud and happy (and I think you are just that!) :wink:
Must rush ..... have to order my teflon caps :rotflmao:
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Hmmmm.....US$97.80 (1uf) and US$17.80 (0.01uf)for the Sonicaps http://www.soniccraft.com/sonicap_platinum.htm plus another AU$47 for the Mundorf http://www.soundlabsgroup.com.au/c/Mundorf-Silver-Oil/Mundorf+Silver+Oil.html
That's about AU$200 plus postage......s'not too bad I suppose. But you wouldn't want to stuff up that 1uf Sonicap.
Or show it to the missus....... :lol:
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Seano - good luck with sneaking them in under the wifey's nose :icon_lol:
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"Sorry sweetie! The stereo is busted at the moment and I'm just getting this replacement part - you know I've explained to you before about the guy who I got the kit from likes to charge big time for the individual parts.........well this one's a bit more expensive than most....and there's just no other alternative [shrugging hopefully]"
:lol: :lol: :lol:
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Problem is if your wife ever saw Hugh at say a party, he might really cop an earful. Alternatively, you could ask Hugh to spec up a GK1 Platinum Super upgrade kit with V-Caps or whatever specified in every possible position. Then you explain how reasonable your modest your $200 upgrade plan was compared to that outrageously priced audiophile upgrade kit. Only problem is, Hugh would then be safe at the party but he might gain a bit of notoriety on the net for having the world’s most expensive preamp kit. :)
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Seems there's no limit to what lengths we audio buffs will go to to upgrade our beloved systems :lol:
Meanwhile, I have ordered my Platinum caps and await their arrival eagerly :drool: :drool: :drool:
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Steve, just been reading your plug for all things AKSA on http://www.high-endaudio.com/RECENT.html#Feb
I have been a keen reader of this site for years and have always enjoyed Arthur's forthright observations on all things audio. Good to see he posted your letter.
Now, can someone who knows post a mod thread for all AKSA's , just what they have changed. Please not a pile of words, just where to get the parts, approximate price and a star rating (very objective I know) to the net worth of the mod.
Mark
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Gee, Mark,
That's a tall order!!
Cheers,
Hugh
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Hugh, I did not mean 1 person. :duh:
Anyone who has changed the specifications can post.
Mark
PS where and what is 2007 RMAF?
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Rocky Mountain Audio Fest, held in Denver CO each year in October.
The best option for the small manufacturer, and the genuine audiophile who is interested to meet and talk with them.
Much cheaper than the CES, specifically set up for the little guys.
Cheers,
Hugh
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Mark,
Most of the mods, along with reasons for trying them, are stored right here in the history of this site. Different people ... different mods, so it comes down to reading through it and evaluating what looks good and what looks iffy. It's an interesting read as much for being a kind of living history of Aspen as much as anything else too.
One of the things I rather like about Hugh's circle is that he's allowed all manner of mods to be discussed but keeps his own thoughts on them pretty much to himself though we'd all love to know his opinion :lol:
jules
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Just got word that my Platinum caps should arrive Monday. Guess I should start heating the soldering iron :lol:
This is going to be interesting - hope I won't be so busy at work next week that there won't be time to put in the caps ....... :oops:
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Platinums arrived right on schedule yesterday :)
I'm currently planning the "makeover" so I won't have to be without my GK-1R longer than absolutely necessary!
I plan to reroute and shield a few internal wires while I have everything apart anyway, but that shouldn't be too big a deal :wink:
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Jens,
I am awaiting news from you after you have some time with the new caps. I heard a difference from the beginning.
One thing to note is that the large 1uf input cap drops the low cutoff frequency enough so that if one has a subwoofer that goes down to 20hz or so one can sometimes hear low rumbles on old recordings.
Steve
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Hi Steve,
Yep, this is going to be interesting. I will report, of course :wink:
I'm aware that increasing C1 to 1 uF extends the "deep end" a bit. Not a bad thing in my book - I love organ music!
One question: On Sonic Craft's homepage it says about the Platinum caps that "The shorter lead is shield". Which lead should preferably go to signal input when inserting the caps?
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Hi Jens,
The shield (short lead) goes toward the RCA and the long lead goes to the input on the board.
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Hi Jens,
The shield (short lead) goes toward the RCA and the long lead goes to the input on the board.
Very good - short lead is signal input. Thanks, Blizzard :D
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Hm, I never really took note of lead length, as they looked about the same. I did notice the writing however. Does the path go in line with the writing, S on input and P on output?
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Nah, it's the other way around, actually. The longer lead (output, as it seems) is at "S" and the shorter (input) at "P".
I wouldn't know how much difference it makes in real life - don't even know what theory is behind inputting the signal at the "shield" end of the cap. Anyway, it seems you got a lot out of these caps even though you didn't know what was "right", so I wouldn't worry too much about it, if I were you :)
Hugh? Anyone? Any thoughts/theories about this?
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Jens,
Shouldn't make any difference, however, email Jeff Glowacki of Sonic Craft and ask his advice.
He's very knowledgeable, and as he sells 'em, he should know.
Cheers,
Hugh
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Hi Hugh,
Very good idea!
I did just that and got a quick reply back from Jeff:
"The idea is that the shield "may" catch some RFI or EMI, so one might
direct the greater source (shield) of "potential" noise to a benign
drain. This drain might be a load resistor such that you would make
the shield the output, but as you suggest, some may prefer the other
direction for one reason or another. It would be circuit/owner
dependent, so that is why we merely convey which lead is which. You
get to make all the decisions. ;~)"
It would seem that soundwise, it may not may make that much of a difference, but that there could be a slight difference in noise. Guess I'll go with the direction of the text, after all :green:
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I have now turned my input caps around so as to take advantage of the shielding. I don't use shielded interconnects, so makes sense to take advantage of the shielding in the caps at the input location.
I don't think it makes any difference in the small caps at C19.
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Now, can someone who knows post a mod thread for all AKSA's , just what they have changed. Please not a pile of words, just where to get the parts, approximate price and a star rating (very objective I know) to the net worth of the mod.
Mark
Mark,
Okay here goes for GK-1:
C1 - Sonic Cap Platinum 1 uf, could also use .47uf ***** a 5 Star MUST
available only at Soniccraft
C19 - Sonic Cap Platinum .01 uf ***** a 5 Star No brainer
C21 - 1uf Mundorf Silver /Oil or Dynamicap **** with the Platinums in place
- 1uf Auricap, the stock cap fits the board, and okay
Gain Stage caps - I have changed most of them to Black Gates, Rubycons, or Oscons in the same values. I didn't honestly hear any difference from doing this. Money is better spent on the above caps.
Tubes - 7308 Amperex 1964 NOS - a nice but small change. *** 3 stars
Get caps first! Stock tubes are quite okay.
Not worth spending a lot of money here, though 7308's are always
expensive.
I purchased from www.vintagetubeservices.com
Attenuators - I use a Goldpoint Shunt 20k attenuator with Vishay S102 for + resistor.
Goldpoint no longer makes kits. Kits only available from Michael Percy
either as ladder or series attenuator.
This may only be ** 2 star as I can't really say I heard anything being
much better.
Rca's etc. - personal preference prevails.
Steve
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I have finally gotten my "Platinum" upgrade to work. And I do say "finally", because it has taken me 3-4 weeks to get my GK-1R back in reasonable working condition after implementing the Platinum caps according to Steven's recipe (apart from one exception).
I haste to add that none of the problems I ran into could be ascribed to any of Steven's advise, make no mistake!
The problems I ran into was hum, hum, hum, and yet more hum!!! Admittedly, I did complicate matters a little myself in that I replaced all signal wiring with my own Equilibrium Cable pure silver wiring at the same time as implementing the Platinum caps.
Anyhow, the first thing that happened after I had put my GK-1R back together, new caps, new wiring and all, I had HUUUUUMMMMMMM! Not devastingly loud, but still loud enough to be heard in my listening position, which is almost 6 metres away from the speakers. The hum was more or less independent of volume setting.
Hmmmm, I thought - this might be because I put the big 1 uF Platinum caps outside the board (in fact, I mounted them with Blue Tack astride two input relays each), causing them to pick up hum. However, moving the caps to the board did not help .....
Do you guys know in how many different ways ground wiring can be done on a GK-1R? Well, during the last 3-4 weeks I think I've tried them all!!!! Also tried various way of earthing (I've got true earth) the preamp. Nothing worked. Hugh and I had some email gander, but none of the things we could come up with worked .....
I won't bore you with all the details of the many things that were tried - suffice it to say that I believe that the main problem has been found. I turned out to be the output cap. Because I wanted to roll off the treble/mid section of my speaker system, which is driven off the tube output, I had reduced the output cap value from the 1 uF Auricap to a .047 uF Sonicap Platinum. Obviously, the latter is a very small size cap, even in the Platinum range, so we are not talking about hum intrusion into the cap (at least I don't think so).
I talked to a tube-knowledgable friend of mine today, who believes that the hum problem I experienced is likely to be caused by the change in the output impedance at the low end of the register, as it becomes easier for hum to be induced into the interconnect between the preamp and the power amp (in my case a LF55) and then possibly back into the rest of the preamp circuits. In my system, this signal wire has always been an unshielded one, which never created problems before. Whether this is the whole story, I don't know ....
I may try out shielded interconnects in this place, but until further notice, the original Auricaps have been reinserted and will stay, as the system is now hum-free :hyper:
All the above being said, I'm not quite out of the woods yet. The process of eliminating the hum involved taking the Relay board out of the "loop" and running wires directly to input and output of the Analogue board. In theory, the Relay board shouldn't make any difference, but previous experience (from when I first built the GK-1R) shows that it may not be as straighforward as all that.
However, the main thing is that now I have music again! Those 3-4 weeks without music were scary!
I haven't had time to listen very much to the differences, but I second Steven's opinion that especially the 1 uF Platinum cap is worth the while. Bass certainly seems to dig deeper and have more slam. The Platinums also seem to render details in a most natural manner. I'll listen some more and report back later if I feel there is more to report. I should add that the improvement is worthwhile and quite pleasing.
If anyone runs into hum problems of the sort I've described above, please do not hesitate to contact me. I guess I've tried most of the things that can be done to remedy hum problems in the GK-1R over the last few weeks, poring over the GK-1R for endless hours.
But now there's lovely music, and all is bliss :singing:
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Jens,
I've been wondering about your Platinums as you've been quiet since receiving them. Now I know.
I don't have a 1R, just a plain GK-1. I've been bugged by hum at times. I've found that it's usually been attributed to solder joints on the source switch. I now run just a single input, and everything is very quiet.
I once had a pair of .47uf Dynamicaps on the output, and had no hum from them. At the final choice I was deciding between 1uf Dynamicap and the Mundorf. A second pair of 1uf Platinums with long leads to the board was too costly for perceived minimal benefit.
I think you find that everything will sound better now that you have music.
Steve
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Jens,
I've been wondering about your Platinums as you've been quiet since receiving them. Now I know.
I don't have a 1R, just a plain GK-1. I've been bugged by hum at times. I've found that it's usually been attributed to solder joints on the source switch. I now run just a single input, and everything is very quiet.
I once had a pair of .47uf Dynamicaps on the output, and had no hum from them. At the final choice I was deciding between 1uf Dynamicap and the Mundorf. A second pair of 1uf Platinums with long leads to the board was too costly for perceived minimal benefit.
I think you find that everything will sound better now that you have music.
Steve
Mmmm, Steven,
I have a GK-1R and absoloootely no hum! But it's not a "stock" GK-1 ... I changed several caps. I don't have Platinums for the input coupling caps ... so that's certainly something I will try in due course.
Next project, though, is to gain brownie points from the "trouble and strife" by putting 3 boxes worth of stuff (3-way active XO, AKSA modules and associated PSes) into one box. because of the effort involved, this must include upgrading to LFs!! :D
Regards,
Andy
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Jens,
Thank you so much for your perseverance. This has been an epic battle. I too am involved on this front, as you know, and still forging ahead. It is very frustrating, because I've built many of these preamps and this is the first that's really been a problem.
Interestingly, even with the output shorted to ground, there is still hum!! This tells me the problem could be ground reference, a weird one indeed....
Cheers,
Hugh
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Hi Hugh,
Still hum when output is shorted? Really weird! Could be the interconnect, then?
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Well, I have now had a chance to listen a bit more to the "Platinum" upgrade of my GK-1R. I have not yet re-implemented the Relay board, and fortunately everything is still really silent!
Except when playing music, of course :lol:
Anyway, I had an audio friend over for a few hours the other day, and we listened to music more or less all the time he was here. This also meant I got to play some very well-known tracks again, which made it fairly easy to make comparisons between "pre-Platinum" and "post-Platinum" sound. I should also mention that I do not believe that the Platinum caps are yet burned in.
However, already now I can safely say that there are things to be had with this upgrade. Listening through a large variety of music the other day, the first thing that struck me was a smoothness that I did not hear before. It is not the kind of smoothness that glosses over and blotches out detail - detail is retained, and indeed to some extent improved.
Also, as mentioned before, there is noticeable more "slam" in the bass. But not only more slam, also more precision. Perhaps bass is also a bit more weighty, but I'll need to listen a little more to verify that.
Coming back to the smoothness, this also extends into the high octaves in a very pleasing manner. As a result of this, spatial information is also improved to some extent - and this was absolutely excellent as it was!
The above could sound as if the improvements are fairly small. I don't feel they are. In fact, I would say they are improvements that are well worth the investment into the fairly expensive Platinum caps. Also, I don't feel that implementing the Platinum caps changes the inherent GK-1 sound, it merely brings it to another level :wink:
I have yet to implement "The simple GK-1 tweak" for C2 from PSP's thread, but this will be done in a not too distant future (have to get hold of the caps for this).
For now, I'll just keep playing and enjoying music from my upgraded GK-1R and see what happens when the caps settle in :)
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Gentlemen,
My initial motivation to modify at C1 and C2 was based on SL's preamp recommendations for the Orion. (I suppose) in order to reduce phase errors at 20Hz, he recommends that the preamp be good down to 5Hz. When I asked Hugh for advice, he recommended that C1 be increased to 2.2uf "a good film cap" and that C2 be increased to 33uf "a good electrolytic". When I made the changes I expected deeper/better bass but was surprised to hear significant improvement across the board, especially in the highs. Just as Jens says, the underlying character of the GK-1 remains, only more better :D. Since then, Steve has pushed this mod to an entirely new level and at some point I will be following his lead with the Sonicap Platinums.
However, I should point out that I changed C1 and C2 at the same time, so I don't know what the sonic impact of change at C2 alone might be (other than Hugh's initial suggestion that it might help extend the bass).
Peter
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Hi Peter,
Good point! Obviously, it's difficult to know how much comes from the improved C1 cap and how much from the improved C2. However, since the "lid is off", I thought I can just as well include the C2 in my upgrade scheme - it certainly won't hurt.
I will try to use a BG NX 33 uF, if possible. However, it does not seem to be available at any higher voltage than 16 V. Does anyone know how much voltage C2 needs to be able to tolerate? Hugh?
Peter, hope your Orion adjustments are coming along nicely :wink:
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Hi Jens
o.k. o.k. you've got me salivating for the mods to my GK-1 and I haven't even begun the build yet! :lol: But maybe I'll just do it from the start as it seems to make a nice difference...
quick question though: did you integrate all SL's mods?
C1 - Sonic Cap Platinum 1 uf, could also use .47uf
C19 - Sonic Cap Platinum .01 uf
C21 - 1uf Mundorf Silver /Oil or Dynamicap
- 1uf Auricap, the stock cap
I didn't see a specific reference to exactly what you were doing.
thanks
jim
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Hi Jim,
I implemented a Sonicap Platinum 1 uF for C1 and a Sonicap Platinum .01 uF for C19. C21 is still the Auricap. I tried implementing a .047 uF Sonicap Platinum for C21, but got hum, most likely because of the large change in value from 1 uF to .047 uF. It seems with this low value hum might get in through my unshielded interconnects between the GK-1R and the LF55. I'm going to try with shielded interconnects at a later stage ......
The change of C21 from 1 uF to .047 uF was intended to create rollof for my treble/mid system at around 250 Hz.
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thanks jens!
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A short note on handling "shields" on capacitors. Many caps have a "shield" end - that being the connection to the outermost plate or foil winding etc depending upon construction of the cap. It therefore has some shielding action - hence the name
To maximize this shielding action and to better drive any leakage capcitance to surrounding parts the shield end should always be wired to the capacitor circuit pad which sees the lowest impedance back to signal ground.
On a GK1 analog board input, the input Z is 47K'ish - the drive from a CD player etc (REGARDLESS of whether it comes via a relay switch board or a manual switch) is likely to be less than 10K so wire the "shield" end to the signal input connector end with the other end feeding the base of that first transistor
On the tube buffer stage input, again the actual tube input is a higher impedance than looking back into the volume control so the "shield" goes to the volume control input side.
On the GK-1 tube buffer output, the tube output impedance will be lower than the input impedance of whatever power amp you hang off the output so in this case the "shield" side goes to the tube cathode and the other side goes to the output socket.
I learned this from building valve (tube non Oz and UK types) amps. In all of my valve amps the coupling cap "shield" side goes to the driving stage anode and the non-shield side goes to the grid of the next stage valve.
Cheers,
Ginger
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Thanks, Ginger! Very good input! All GK-1 owners wanting to upgrade should be able to take advantage of this! :wink:
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just ordered my platinum caps... couldn't resist :drool:
going through the build right now... gotta say (again) that hugh's instructions are excellent. :thumb: Everything is going smoothly!
jim
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Well, I finally got around to upgrading the caps in my GK-1 about 5 weeks ago and have around 400 hours on it since then.
Specifically, the upgrades were:
C1, C19: replaced with Sonicap Platinums
C21: added a Sonicap Platinum bypass cap across the existing Auricap
C2, C4: BlackGate N/NX
The improvements were fairly evident immediately and opened up a little more over the next few weeks...
Quieter noise floor, greater transparency
More ambient/acoustic info
Greater inner detail (especially evident in bass chords)
Tighter, cleaner bass
Less mechanical sounding, more natural/organic/musical/real
Instruments with complex harmonics sound more realistic (piano, violins, cellos, basses etc)
Soundstaging has a little better dimensionality
More nuance in voices
More realistic and sweeter upper mids & treble
Individually, each improvement is subtle, but the overall improvement is well worth the money and effort IMHO. For a few hundred dollars it takes the GK-1 up another notch. I haven't heard any A$10k+ pre-amps but my GK-1 easily matches all pre-amps I've heard up to A$7500. Though I wouldn't go so far as to describe the scale of improvement as being equal to a major component upgrade, I think it would be fair to say that it was equal to a minor component upgrade.... and for anyone eager to glean every last iota of performance from their system, that's not bad for a few hundred bucks!
It had already been modded with TKD 2P65S stepped attenuator (http://www.thlaudio.com/indexE.htm (http://www.thlaudio.com/indexE.htm)) & Vishay S102 bypass resistors, Vampire OFC RCA's, twin grounded shielding plates, Dynamat Extreme damping material on chassis, damped PCB mounts, NOS Siemens gold pin 7308 tubes, no source switch in signal path, etc.
Every time I think that I've got the very best that Hugh can do, the bugger comes up with something better. So, I know I shouldn't do this but ...
Hey Hugh, I challenge you to come up with something even better! :duh: :duel:
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Thanks Darren,
Thinking all the time..... :oops:
But also thinking about more sales!! :duh:
I hate that part of it, seems somehow messy, not pure, like the engineering...... :roll:
And there lies the rub.......:deadhorse:
Cheers,
Hugh
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Well, I finally got around to upgrading the caps in my GK-1 about 5 weeks ago and have around 400 hours on it since then.
Specifically, the upgrades were:
C1, C19: replaced with Sonicap Platinums
C21: added a Sonicap Platinum bypass cap across the existing Auricap
C2, C4: BlackGate N/NX
The improvements were fairly evident immediately and opened up a little more over the next few weeks...
Quieter noise floor, greater transparency
More ambient/acoustic info
Greater inner detail (especially evident in bass chords)
Tighter, cleaner bass
Less mechanical sounding, more natural/organic/musical/real
Instruments with complex harmonics sound more realistic (piano, violins, cellos, basses etc)
Soundstaging has a little better dimensionality
More nuance in voices
More realistic and sweeter upper mids & treble
Individually, each improvement is subtle, but the overall improvement is well worth the money and effort IMHO. For a few hundred dollars it takes the GK-1 up another notch. I haven't heard any A$10k+ pre-amps but my GK-1 easily matches all pre-amps I've heard up to A$7500. Though I wouldn't go so far as to describe the scale of improvement as being equal to a major component upgrade, I think it would be fair to say that it was equal to a minor component upgrade.... and for anyone eager to glean every last iota of performance from their system, that's not bad for a few hundred bucks!
It had already been modded with TKD 2P65S stepped attenuator (http://www.thlaudio.com/indexE.htm (http://www.thlaudio.com/indexE.htm)) & Vishay S102 bypass resistors, Vampire OFC RCA's, twin grounded shielding plates, Dynamat Extreme damping material on chassis, damped PCB mounts, NOS Siemens gold pin 7308 tubes, no source switch in signal path, etc.
Every time I think that I've got the very best that Hugh can do, the bugger comes up with something better. So, I know I shouldn't do this but ...
Hey Hugh, I challenge you to come up with something even better! :duh: :duel:
Hi Darren,
Yup, sounds like you've had the same success with the Platinums that I had. The Platinums certainly make all the music better.
Steve
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Steve, it is largely your observations that pushed me over the edge. So, I guess it is I that should be thanking you. :D
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Steve, it is largely your observations that pushed me over the edge. So, I guess it is I that should be thanking you. :D
Darren,
I'm pleased that you've found the same improvements as I did.
It didn't really take much of a nudge, did it?
Maybe we both should thank Jeff for designing the cap and making it available to us.
I would hope many others would/will take the big leap!!!!!!!!!!!
Steve
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Steve, Darren,
Swapped out C1 for Platinum teflons in Raptor's Swift yesterday - I'm hoping he will post here with his observations. For myself, I've noted improvements in transparency and fine detail, well worth the effort but still a little dazed by the cost......
Cheers,
Hugh
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Hi Hugh,
I've only listened to it for a couple of hours, but my initial impression is that it has improved the amount of detail I can hear, and the soundstage seems wider and a little deeper. What has surpised me is that somehow it has improved the bass response I am getting. As you heard when you delivered the Swift to me originally, my system was light on for bass which I put down to speaker positioning and the room itself. This was an area I knew I had to address to get the most out of my gear, but I hadn't got around to experimenting yet.
However as soon as I arrived home and connected the Swift yesterday I put on the Copeland cd we were listening to at your place. The improvement in the bass was quite striking; it had become much more prominent and was now in balance with the midrange and high frequencies, an unexpected bonus.
I will post more when I have had an opportunity for more listening and will try to post the photos that I took when I can work out how to do so here.
Cheers,
Neil
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Hi Neil,
Wow!! That was quick - thanks for the response!
So, we have more bass, huh? That's a surprise to me, I had not expected more mumbo, and it addresses one of the perceived deficiencies of tube systems.
I'm sheepish about those photos; you caught me in the appalling disarray of my workshop!
The increased refinement and detail is always welcome, what this game is all about. Thanks for your visit yesterday, a pleasure to chat over coffee and walnut slice, and do please tell us how it 'beds' down!
Cheers,
Hugh
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Hi Neil,
So, we have more bass, huh? That's a surprise to me, I had not expected more mumbo, and it addresses one of the perceived deficiencies of tube systems.
Cheers,
Hugh
Hi Hugh,
I thought the "perceived deficiency of tube systems" wrt bass was softening of bass transients ... as shown by the increased bass punch available from the GK-1 "Sub Out", compared to the normal tube out.
Not lack of low frequency extension - which is what I assumed Neil would've been referring to?
Anyway, sounds like I'll be inserting teflon coupling caps in my GK-1 when I've finished my upgrade to Lifeforces! :D
Regards,
Andy
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Andy,
Of course - you are right!
Hugh
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However as soon as I arrived home and connected the Swift yesterday I put on the Copeland cd we were listening to at your place. The improvement in the bass was quite striking; it had become much more prominent and was now in balance with the midrange and high frequencies, an unexpected bonus.
Cheers,
Neil
Hi Neil,
When you say "The improvement in the bass was quite striking; it had become much more prominent ...", are you talking about:
* an increase in the level of bass compared to the rest of the frequencies (IMO that's what you appear to be saying?)
* bass was extended lower, or
* it was crisper bass?
Regards,
Andy
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Individually, each improvement is subtle, but the overall improvement is well worth the money and effort IMHO. For a few hundred dollars it takes the GK-1 up another notch. I haven't heard any A$10k+ pre-amps but my GK-1 easily matches all pre-amps I've heard up to A$7500. Though I wouldn't go so far as to describe the scale of improvement as being equal to a major component upgrade, I think it would be fair to say that it was equal to a minor component upgrade.... and for anyone eager to glean every last iota of performance from their system, that's not bad for a few hundred bucks!
It had already been modded with TKD 2P65S stepped attenuator (http://www.thlaudio.com/indexE.htm (http://www.thlaudio.com/indexE.htm)) & Vishay S102 bypass resistors, Vampire OFC RCA's, twin grounded shielding plates, Dynamat Extreme damping material on chassis, damped PCB mounts, NOS Siemens gold pin 7308 tubes, no source switch in signal path, etc.
Since Darren brought up the subject of price comparing, I thought I might inject some points here.
The price of the GK-1/Swift is that of a direct marketed unit. To compare to a dealer distributed unit, one needs to multiply by a factor of 2X or 2.5X, as dealers/distributors need their cut. Premium cap upgrades usually increase price by as much as 5X of the cost of the caps, just look at what manufacturers charge for these upgrades compared to the cost of the caps. And there are other custom modifications from stock that can be configured at at least 2X parts cost.
Thus, the cost of the GK-1/Swift easily is in the price territory of what Darren mentions, if not more, if one considers that a $10K AUD product is imported and customs/duties/shipping is figured into that cost, thereby making the GK-1/Swift comparitively more expensive.
A lot of factors go in to the cost of a product. I know we all do price comparing as we all fall in to the trap of thinking that a more expensive product must be better. But one has to be careful with this, especially when one is in the world of diy/modification/direct marketed products.
I've heard a lot of preamps, either as personal purchase, dealer auditions, or shows. And I find the Platinum modified GK-1/Swift to be performance wise with the best of the whole lot. It's just that you don't get to brag about how much money you spent!
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Hi Neil,
When you say "The improvement in the bass was quite striking; it had become much more prominent ...", are you talking about:
* an increase in the level of bass compared to the rest of the frequencies (IMO that's what you appear to be saying?)
* bass was extended lower, or
* it was crisper bass?
Regards,
Andy
Hi Andy,
The most noticeable thing was an increase in the level of bass, with further listening it is crisper than before ( as is the whole frequency spectrum), but this is more subtle. Somehow adding the caps has brought my bass into balance with the rest of the frequencies, and I have no idea why this should be so. :scratch:
I live with my 91 y.o. father whose hearing is not good. With the caps added his reaction was that he could make out more of the vocals than he was able to previously, so there's another vote for more clarity and detail :D
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Hi Neil,
You commented on your Dad's response; until six years ago I had a wonderful neighbour in his mid-eighties with very good hearing, probably as good as mine. He was a lovely old man, had a hard life, but with a natural curiousity and a very philosophical approach. He'd been a metal worker, then ran a succession of small delicatessens with his wife, then became a taxi driver. Loved cars! He'd even been a bookmaker at one time!! Ted had a great interest in my amp work, and would always ask to audition each new design.
He could pick 'em too. We never disagreed. Once he said, 'That one is loud, clear but mechanical sounding. The other one is more natural, more like musicians playing'.
He was born in 1915, lived through the Great Depression....... Sri and I visited his widow yesterday, who at 92 has just come through major illness and now lives in a Nursing Home.
The response of the bass and balance you remark upon is very likely due to the much lesser dielectric absorption of teflons over the Evox-Rifa caps originally used. Evidently when an AC signal moves through a cap there is a charge migration across the plates, to and fro, in step with the signal. If some of that charge is slow to move through because it's actually absorbed by the insulating medium between the plates, and released a tiny interval later, then the result is usually smearing, and loss of definition. This is often frequency dependent - some caps are 'faster' than others - and this likely explains at least what is happening at the sonic level. The geometry of the cap is significant too in this phenomenon, as it subtly affects the parasitics - resistance, and inductance - which have impact on the sound quality as well.
Cheers,
Hugh
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What has NO impact on the sound?
Magnet wire theory described by the anti cable designer shows what a big disastrous influence the insulation has even on the "least" sensitive connection in the chain: the speaker wire ( except form power cord) so what about the more sensitive connections?
The cabinet influences the sound in a BIG way
the nature of the metal in the pcb connections..
Now it appears pure gold interconnects do sound better than silver (http://www.stereomojo.com/KCI%20Silkworm%20review/KCISilkwormCablesReview.htm ) and poor aluminium probably the worst, probably lead as a pure conductor will sound awful but still better than rust
I would love to hear the GK-1 and LF2, components soldered on a wooden pcb with pure gold paths :green:
wait
i can "copy" the component layout of the GK-1 pcb on a flat spruce board of 3mm thickness, bore holes according to the topology draw the paths on the wood at the underside and do point to point wiring with thin single gold (24 krt) wire insulated in oily "virgin" paper and then varnish the underside with C39 hmm.
i will need ( a guess) 60cm or less gold wire
that will cost 140 us $:
Product Number '1567'
- Product Code: Au-wire010-01
- Unit Price: $ 70.00
- Material: Gold
- Subcategory: 99.99% Pure Gold Wire/Rod
- Diameter: 0.010 in. (30 gauge) (0.254 mm)
- Length: 1 ft. (0.305 m)
- Unit Shipping Weight: 1.00lb.
- Purity: 99.99 %
:scratch:
I dare to predict
This WILL SOUND BETTER :drool:
But The LF2 needs a tad bigger gold wire a tad more expensive but much cheaper than a KRELL
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I can "copy" the component layout of the GK-1 pcb on a flat spruce board of 3mm thickness, bore holes according to the topology draw the paths on the wood at the underside and do point to point wiring with thin single gold (24 krt) wire insulated in oily "virgin" paper and then varnish the underside with C39 hmm.
Great concept, Kyrill mon ami, but can I suggest a better/easier alternative? :D
Instead of using 3mm spruce board ... use 3mm teflon sheet. You can buy it in quite a few sizes (I bought cheaper offcuts here in Oz from a hi-tek plastics distributor).
That is what I have used for making up Hugh's PSes for my active XOs and my phono stage. The teflon sheet is easy to saw, to drill and it doesn't dry out or warp ... also it doesn't melt at soldering iron temperatures. I use point-to-point wiring on the underside ... not gold wire, merely copper - but if you want to go to that extent, then be my guest! :D
Regards,
Andy
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ah haaaa !! what a splendid idea :D
Teflon IS better than the usual pcb plactics or fiber glass,
but, butt, butte Andy,
is teflon's resonance property hearing wise SWEEEET? Does it add this tube like life like warmish support to the sound like wood is always doing?
I mean how would a teflon Cello sound? A piano cabinet of Teflon?
Because i can never damp to zero the vibrations of the amp ( enclosure and pcb/s) I will have to accept those vibrations. But the carrier or medium of those vibrations is in this case the PCB. So this carier will add its "tone" to those vibrations. And from wood ( spruce, maple) it is proven this "tone" supports the music maybe the best way unwanted vibs can do. Some expensive carbon composites may work also)
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ah haaaa !!
Teflon IS better than the usual pcb plactics or fiber glass, but, butt, butte Andy,
is teflon's resonance property hearing wise SWEEEET? Does it add this tube like life like warmish support to the sound like wood is always doing?
I mean how would a teflon Cello sound? A piano cabinet of Teflon?
Because i can never damp to zero the vibrations of the amp ( enclosure and pcb/s) I will have to accept those vibrations. But the carrier or medium of those vibrations is in this case the PCB. So this carrier will add its "tone" to those vibrations. And from wood (spruce, maple) it is proven this "tone" supports the music maybe the best way unwanted vibs can do. Some expensive carbon composites may work also)
But butt butte buttte to you too, by Dutch friend, Kyrill!! :D
I'm afraid I agree with some of what you say ... and disagree with other parts! :thumb:
In terms of wood "proven" to support the music by its tone ... yes, sure - with a piano sounding board or a violin backboard or frontboard, etc.. These are musical instruments; the wood "tone" is required, in order to generate their sweet sound.
However, as a support for components ... I'm sorry, I just can't agree that it must sound better. :D However, I am prepared to agree that a circuit made from 1/8" spruce or teflon board, point-to-point wired on the back will sound better than a conventional PCB. However, whether the spruce board will sound better than the teflon board - that you have to prove to me by making up two identical circuits - one from teflon and one from spruce/maple. And when you have, I'll pay for a flight over to come and listen! :D
And re. carbon-composites:
* on a hifi forum recently, I saw a picture of a CF-composite cello which Yo Yo Ma plays. I presume it must sound very nice - otherwise he wouldn't bother! Therefore, I'm prepared to believe that a PCB made from CF-composite may well sound good ... but, as you say, it's probably an expensive exercise! :D
* I sell a CF-composite subchassis and armboard for the good old Linn LP12 turntable (which is a replacement for the stock, pressed-steel subchassis and MDF-based armboard) which dramatically improves the sound of the LP12 ... so CF-composites can indeed do good! However, the improvement from the CF-composite subchassis IMO is not due to any "beautiful tone" it has ... but rather, simply that because it is stiff and light, it doesn't have any of the vibration problems which are inherent in the pressed-steel subchassis. So it's simply hard physics, not wishy-washy greeny thinking! :D
Regards,
Andy
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my wife has a gold chain she never uses, maybe. . . :i :oops:
what i mean why wood resonances influences component, at least as i understand it.
Thru the components is a complex signal build up "contaminated" by eddy currents. These eddy currents are 100% consistent with the "movements" of everything conducting electrons in a magnetic field be it static or dynamic and or moving metal in an electric field creating on its turn a dynamic magnetic field and or moving electrical fields creating in static metals a dynamic magnetic field.and so on. Eddie currents also induce magnetic fields.
Many doorbells are based on the principle of making a magnet by an electrical current around a piece of metal.
It all INTERACTS in a complex soup. I say eddie currents but in the broadest sense. Strictly speaking eddie currents labels only local circular currents
So for instance a vibrating resistor will create an extra minimal current if under a (dynamic) magnetic field. this extra current will be 100% "toned" by the tone of the mechanical force controlling the resistor (= vibrations by air and pcb)
Consider the whole pcb to be a moving grid with multiple nodes. Nothing is static, all the nodes, connections vibrate, the whole pcb vibrates. But the heaviest mass dictates the nature of these vibrations (tone). That is why the heaviest mass must be the wood, mechanically coupled to the pcb.
Where do the vibrations in amps mostly come from?
From the air in the room unless you are so naive as to put the amps on top of the speakers or the speakers on the same shelf as the amps and source.
The magnetic fields and electrical fields are not uniform but do interact with each other.
These minimal currents are amplified in the amplifier as well and they are not separated noise as if in a different plane but are fully integrated in the musical signal itself They tone the music, you don't hear it as noise. This tone is extremely important and proofs empirically by hearing that eddy currents maybe very very small in measurements but can be heard as tone very easily.
That is why Altmann insists that the wooden board directly under his amp and dac are necessary and are an integral part of the design and cannot be removed or else you loose their magic for a great part. That is also why he detests cavities inside amp and dac enclosures. these cavity resonances add ugly "tone"on top of the above story. They negatively impact the "openness" of the sound.
Another hint is the effect of dampers under sources or amps. They only damp vibrations and resonances and nothing else . Why can you hear their effect so easily? This has nothing to do with microphonic FB. Microphonics is of a much much bigger voltage and current levels
I give Altmann right. The effect I hear is very much more pronounced than differences in IC's or even power cleaning.
It is in the same league as the difference between tubes and SS. Once hearing the difference i cannot go back. . I am convinced if end transistors like in the AKSA or lF would be cooled by copper or even better special designed pressed carbon heat sinks, the sound would make a big leap for the better
Too much however, too much vibrations even with wooden tone, add cloudiness and robs the transparency and focus away. Just like salt in a superb soup. The salt adds to the soup but too much will rob the soup.
The wood resonances somehow "correct" the ugly metallic "default" tone of eddy currents. as eddy currents are created by metals
btw the choice for wood is of course NOT meant to dampen the vibrations. but to use its resonance properties. damping is apart from it. For instance add mass and special gadgets for damping like special feet. But be be carful with heavy damping sheets l.They may not be too heavy relative to the wooden mass or they add their own UGLY tone.. ( closing the sound in and introduce something that robs the live likeness high end turning to hifi) )
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*.....which dramatically improves the sound of the LP12 ... so CF-composites can indeed do good! However, the improvement from the CF-composite subchassis IMO is not due to any "beautiful tone" it has ... but rather, simply that because it is stiff and light, it doesn't have any of the vibration problems which are inherent in the pressed-steel subchassis. So it's simply hard physics, not wishy-washy greeny thinking! :D
Regards,
Andy
Maybe ,Andy man :P
You could make a rigid light aluminum frame for the LP12 or from a special rigid and light plastic ( from a mall) and i can guarantee you the carbon based will sound better. That is why aluminum or titanium Cello's will NOT sound musical pleasing,
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Maybe ,Andy man :P
You could make a rigid light aluminum frame for the LP12 or from a special rigid and light plastic ( from a mall) and i can guarantee you the carbon based will sound better. That is why aluminum or titanium Cello's will NOT sound musical pleasing,
And yet, Mark Knopler's shiny metal (aluminium?) guitar which features on the cover of one of Dire Straits' albums ("Brothers in Arms"?) sounds fantastic!! :?
Regards,
Andy
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Andy,
Please be nice!
Hugh
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Interesting to note that I think Mark Knofler only used that "National Style 0" guitar for one song. "Romeo and Juliet". And the guitar was designed in the 30's I think.
Russ
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Andy is almost right when he says: "....the improvement from the CF-composite subchassis IMO is not due to any "beautiful tone" it has ... but rather, simply that because it is stiff and light, it doesn't have any of the vibration problems which are inherent in the pressed-steel subchassis."
I say "almost right" because one of the goals of the designer of an acoustic stringed instrument is too create a sound board that is infinitely stiff and infinitely light so that it will vibrate easily without dissipating any energy as heat. Carbon fibre composites perform better in this respect than wood, hence the emergence of composite violins, cellos, and basses in recent years.
However, this is the opposite of what we want in the chassis of a turntable or an electronic circuit. Here we want a material that is infinitely damped so that it wont vibrate at all, but will absorb any energy that comes its way. If you really believe that mounting a circuit on a piece of wood makes an audible difference, try potting it in silicone instead...
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ah it is all in the ears...
I have a potted preamp ( Klyne 7) all the active elements are potted also to keep the design secret.
a second alternative and more easy is put the speakers in another room and the doors closed..
it is still less musical then with a "touch" of wood :green:
The proof is in eating the pudding :D
I invite you to experiment
PS i dont belief that heat emiision has anything to do why a signal sound pleasing to the ear.brain, so it cannot be the reason why stiff carbon violins will sound better IF they do than wooden violins. wood and carbon share tone because of their similar high carbon structure, nothing to do with heat
Our ear/brain is not a science instrument it has its human subjective references ;)
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Kyrill wrote:
ah it is all in the ears...
- and, I would add, the human brain.
The way we process and perceive the sound is probably as important as the sensor! :roll:
It's fair to say, I think, that as far as their music goes, many prefer a painting to a photocopy - and this explains the love of the single ended triode amp which is technically a doddle but psychoacoustically a masterpiece. Since we can't make a push pull SS amplifier which matches the distortion spectrum, we are literally forced to design one with vanishingly low distortion because the SS AB push pull distortion spectrum is perceived to be most objectionable by the ear-brain interface. :finger:
If we listened to test tones, it would be no problem. But we listen to music, it is an artform, and we like it to stop us talking to each other, and make us weep. This is a tall order for a man-machine interface. :lol:
Cheers,
Hugh
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Just tracking the thread back to the Sonicap Platinums for a moment; picked my GK1 up last night from Hugh, whom I had commissioned to do the upgrade. I understand he did C1 alone and used 0.33uf caps to keep the cost half reasonable. I’m glad he did but I still won’t be buying too many CD’s this week. :roll:
Whilst the technicalities go way over my head, the sound improvement hasn’t and without as much as 5 seconds of break in time, the improvement was amazing. Little point at restating too much of what has previously said by others such as Raptor but the increased clarity, reality and dare I say richness across the spectrum, was immediately noticeable. Like Neil, my attention was first drawn to an improved heft in the base but I am convinced on further listening the biggest improvement overall whilst well across all frequencies, was in the treble. Again seemingly repeating Neil’s impressions, the level of base is now just right and in addition in my case, the treble – all seemingly in perfect balance.
Further though, the musicality improvements that stem from the greater transparency and detail encompass a more natural, realistic, harmonic structure that must be awfully close to the recorded event. The 3 dimensional reality of the sound stage is quite stunning but I don’t truly know what part of the balancing act is supplied by the GK1 and what part from the LifeForce. I know I have a good CD spinner, speakers and room but the heart of the system is the amp and the soul is the pre and for both of those I am indebted to Hugh. The amp I need to say more about in another post but the point of this one is that the soul of my system is in top shape. Take a bow Mr Dean. :thumb:
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Finally got around to putting some pics of my GK-1 in my gallery.
Pls excuse the streaky appearance of the stainless steel chassis, I was out of Acetone (and it actually appears much more obvious in the pics than real life). :oops:
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DSK
Awesome! Your GK-1 Platinum looks like a knight in shiny armour! How thick is your stainless steel plate?
Best Regards
Dennis
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DSK
Awesome! Your GK-1 Platinum looks like a knight in shiny armour! How thick is your stainless steel plate?
Best Regards
Dennis
Thanks Dennis. It is 2mm thick stainless steel with 5mm thick front panel. All laser cut, including all the holes. Looks great when given a good wipe over with Acetone but does show fingerprints etc quite badly.
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Finger marking is easy enough to fix.....but it means pulling apart your case. Take the parts to a powdercoater and ask for a clear coat. Be unlucky to cost more than $50. A slightly more expensive alternative is to take the case parts to a spray shop and get a clear baked enamel coat over it....
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Hi DSK,
An easy way to protect stainless steel from the grubby paw marks.
I have found that Wattyl pressure pack Incralac clear lacquer makes a good job of protecting most metals. I have used Incralac on stainless and brass boat fittings. It has lasted two to three seasons in the elements. However, if the coating is scratched, really scratched through to the metal allowing water to ingress between the coating and stainless steel fitting, the coating peels off over time.
I have coated stainless exterior car trim with success. It has lasted five to six years and still looks good.
Coatings in general don't like to stick to stainless steel unless a specific primer or undercoat is used. Since the face plate on your amp is used in a light duty environment I think that the Incralac should last for years provided you prepare the face plate correctly. All coatings are usually affected by fingerprints and natural body oil. It is the acid in the finger print/oil that attacks coatings or inhibits the coating from bonding.
Remove the face plate and clean it thoroughly with acetone, rubbing in a circular motion to make sure that there are no blemishes or rainbow smears. And then rinse liberally with acetone and dry off with a soft clean soft cloth wiping on one direction only if the plate is highly polished.
Try spraying the Incealac on the back side of the plate for practice. It covers very well.
Three of four coats an hour or so apart (read the instructions) will see the job done quickly. If you are a good sprayer with a pressure pack you can heat the pate to about 40 to 50c allowing you to apply four coats in about fifteen minutes.
The Increlac costs about $18 per can from memory and is available from most paint shops, particularly Wattyl shops.
Good luck,
Laurie
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Laurie,
Many thanks for this invaluable advice!! The voice of experience.... :bowdown:
Folks,
TLiner is the man behind the design of the VSonics. I commissioned the design almost a year ago now, we are just now obtaining the final bits and pieces, all the documentation is done, and when the first kits go out I'm confident people will realise the man is a genius!! :thankyou:
Cheers,
Hugh
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Sean and Laurie, thanks very much for the tips. I might have a go at this next time I'm opening up the GK-1 for some reason. Cheers!
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Looks good Darren and not at all streaky :thumb:
Maybe you could just give the case a mild electrical charge to keep fingers away after you've polished it :)
jules
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Maybe you could just give the case a mild electrical charge to keep fingers away after you've polished it
....this'd be no fun if it doesn't leave burn marks
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Seano,
It is nice to have you in the forum...... seldom does one see a man's head more elegantly located.
If Darren electrified his GK1, he would spend his evenings looking like young Einstein.
Sean, forgive my crass comments about Rovers - I grew up in a house with many Japanese curios and was raised on Rovers and Land Cruisers, I just love that 4 litre V8 Lexus motor, it's a corker.
Hugh
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boys and toys,,
when do we grow up?
Where are the serious grown up men?
why can't i find them in heaven?
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Kyrill,
Boys never grow up! They always love gadgets and things which whirr and spin...... and things which are very powerful.
Do you see a primordial link?
Hugh
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primordial link?
with things who are soft and smell like dark wood and places of comfort..
yeah i can see the primordial link :scratch:
but roaring V8's and perfection in searching is my heavenly link :green:
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If Darren electrified his GK1, he would spend his evenings looking like young Einstein.
Sean, forgive my crass comments about Rovers - I grew up in a house with many Japanese curios and was raised on Rovers and Land Cruisers, I just love that 4 litre V8 Lexus motor, it's a corker.
And his children (if they exist) would smell like burnt toast...
There is no such thing as a crass comment about the various breeds of Rover, Land Rover in particular. To be honest, I am not wedded to the Rover V8 as a motivator......perhaps a Toyota motor might be the go!!
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OT, forgive me folks!!
Sean, the Lexus V8 has just over 205 lb.ft of torque at 1000rpm, this is 84% of the max torque at 4,500rpm; an extraordinary figure given it's a modern emissions motor. I remember a 3.9l FJ135 Landcruiser only had 217 ft.lb maximum at 2000 rpm back in the sixties - with a much longer stroke, too. The latest 5.7l V8 fitted to the Tundra built in the States is 401 ft.lbs max, but again, more than 320 ft.lbs at 1000 rpm. This all means very tall gearing is possible with low fuel consumption. All the swaps of the 4l into the Cressida I've seen actually return better economy in the city than the six - it is perhaps a shame all this has come so late in the game, when the very availability of gasoline is threatened by global warming and depleting supply. I don't see fuel cells, batteries or nuclear power sources stepping up to the plate to take the place of gasoline engines, and this could have draconian consequences in the next thirty years.
You will be alive then, let me know how it goes, huh? :lol:
Cheers,
Hugh
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Getting back on track here, afterall, the title is GK-1 Platinum, not Toyota engines..........
There are now more options for those wishing to make a Platinum upgrade to their GK-1's. When I installed the Sonic Platinums the only choices were VH Audio TFTF and Sonic Platinum. Well, there are more choices now:
Teflon Film/Foil:
Reliable
V-Cap
Solen
Penta-cap
ModWright
Audience
Teflon Hybrids:
Sonic Platinum
Cardas Golden
Given the above list, perhaps the Platinums are a little more cost friendly as they are hybrids. I have no idea if a teflon film/tin foil cap is better. These, from any of the above, do cost a fair bit more than the Platinums. One can mitigate the cost by using a .47uf cap on the input, and only doing just that one. The input cap does seem to have the greatest effect as everything is downstream from it. If one is not worried about the bass cutoff, then a .33uf cap could be used. I know Hugh has done that.
The Audience caps are the newest on the block, as I just learned of them a week ago. They also come in a 200v size. Nonetheless, they are very costly. However, a very small Audience teflon could likely bypass the stock Auricap with some effect.
For those with unmodified Gk-1's and/or those still undecided, more choices don't really make it any easier. But, which ever cap you go with, they're worth it!
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Given that I'll be doing the Platinum upgrade to my unmodded GK-1 before I do anything with the Range Rover........this is a timely and damn useful return to topic. So much choice!!!
Hugh, could you distract yourself from Cressida's for a moment to create a summary Platinum sticky??
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Seano it speaks for itself
but if you put an expensive cap (100 US $ 1uF Platinum) on C1 of the GK-1
remove the probably much less transparent and musical output cap of your source ( if there is one)
the difference is not subtle if you replace that output cap with a wire.
Is there a relay at the output of the source probably the output cap is before the relay. In that case
reverse the situation
make that prior-to-the-relay output cap a Sonic Platinum and a wire bridge for the C1 of the Gk-1 other wise dc glips thru the input caps of the GK-1 as relay clicks
repeat this process for the GK-1 out and amp in: wire bridge at power amp input cap and a good film cap for the GK1 at C21
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Time for a Platinum update:
I've now been able to combine my Platinum LifeForce 55 with my GK-1 Platinum preamp. This is definitely the way to go!!! The tubed output stage of the GK-1 really compliments the LF amp in a wonderful way. After months and months of living and listening to the LF straight from the source player, I have to say that it's all much better run thru the GK-1.
I've also left all the Platinum caps in, although having an input Platinum on the amp is a bit redundant since there is a Mundorf silver/oil on the preamp output. I just can't be bothered to shuffle all the caps around and take the Mundorf's out. I just don't think anything much would noticeably change.
There still are not many preamps in the marketplace using premium teflon caps as in this application on the GK-1. And the ones that are out there, cost a whole lot more. I think a Platinum configured GK-1 is one of audio's biggest performance bargains out there. Everyone should have one!
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Couldn't agree more. I was happy with the original GK1 but whilst I couldn't quite put my finger on it, I felt there was something not quite perfect that could be improved. No such thoughts after the Platinum upgrade. I now feel its become the true soul of my system and quite indispensable.
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Hi all.
Here are the upgrades I'm thinking of doing to my GK-1m.
It will be used with orions, so I'm trying to make it possible for the GK-1m to go down to 5hz.
C1 - Sonic Cap Platinum 2.2uF
C2 - 33uF BlackGate N/NX
C4 - 68uF BlackGate N/NX
C19 - Sonic Cap Platinum .01uF
C21 - Sonic Cap Platinum 1uF
what do you all think?
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Hi all.
Here are the upgrades I'm thinking of doing to my GK-1m.
It will be used with orions, so I'm trying to make it possible for the GK-1m to go down to 5hz.
C1 - Sonic Cap Platinum 2.2uF
C2 - 33uF BlackGate N/NX
C4 - 68uF BlackGate N/NX
C19 - Sonic Cap Platinum .01uF
C21 - Sonic Cap Platinum 1uF
what do you all think?
HI,
The largest Platinum cap is 1.0uf, so go with that, or .47uf, for C1.
C2 and C4 make no difference.
C19 is a no brainer with the .01uf Platinum
C21, a good cost effective option here is to get the new Auricap Teflon cap, Auri-T, in a .01uf value and bypass the stock Auricap. This also keeps things on the board rather than off board mounting and long leads. I may do this one myself, if I ever feel like working on the Gk-1 some day.
Steve
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alrighty, so no C2, C4.
For C1, Hugh recommends a 2.2uF cap so that it can go down to 5hz. What do you recommend for a 2.2uF high quality cap, or do you think that its not worth going to 2.2uf, and that I should just stick with the 1.0uF.
For 21, I might consider the Auri-T bypass, but is there a cap that will improve the sonics, but can be replaced into the board without long leads (ie...it fits the board?)
Thanks
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alrighty, so no C2, C4.
For C1, Hugh recommends a 2.2uF cap so that it can go down to 5hz. What do you recommend for a 2.2uF high quality cap, or do you think that its not worth going to 2.2uf, and that I should just stick with the 1.0uF.
For 21, I might consider the Auri-T bypass, but is there a cap that will improve the sonics, but can be replaced into the board without long leads (ie...it fits the board?)
Thanks
Hi,
It's just my opinion that cap changes on C2 and C4 make no difference. I think I have some kind of Black Gate at C2, and have had a couple different ones at C4. They never seemed to make any difference to me. Teflons at C1 and C-19 trumped everything!
Hugh recommended the 2.2uf cap at C1 before he heard my Platinum modifications. The only thing equal or better than a teflon cap at C-1 is a bypass wire. With a teflon cap you have no safety worries of stray dc. Both the 1.0uf and .47uf caps are large and don't fit on the board. Just mount them as input wires and use wire link across the C1 space on the board.
For C-21, there is no replacement cap that fits the same size on the board. I've got some huge Mundorf cap there, mounted off the board with long leads to the board. I didn't really hear any difference with it from the auricap or dynamicap I had used previously. That's why I like the small teflon Auri-T as a bypass as it can be mounted on top of the stock Auricap. It likely won't make much difference, but will give you the feeling that you've done something and improved it by doing so.
Steve
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West,
I strongly support Steve's POV here; the only cap that really seems to make a difference is the input cap, C1, though the output coupler (the yellow Auricap) will have a discenible effect but can simply be enhanced with a teflon bypass, say 0.1uF.
That input cap is VERY influential, as an appreciable AC current does pass through it. The interstage coupler, C19, drives only a tube grid, and passes no current. The polystyrene supplied is a very good cap, tiny too, and can't much be improved upon.
The GK1 as it stands is capable of extraordinarily high performance sonically, out of all proportion to its relative simplicity, and I have been trying for six years to improve on this circuit with very little success.
Hope this helps, and thanks Steve for your input,
Cheers,
Hugh
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Well, it seems like it will just be the C1 for me then.
Thanks for the help!
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forgive me for saying it so often
the C1 cap is coupled to the output cap of the apparatus in front of it.
a dedicated C1 cap makes the function of the output cap prior to to the C1 useless
so remove it as it will (serious) degrade the sound unless it is also a hugely expensive film teflon cap but will still sound less than a straight wire
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Isn't putting a straight wire there a bit dangerous?
I have not modded any of my sources (yet), and I'm not sure I trust the output caps on the Zune or Sangean.
Do you think its better to replace the output cap on all my sources rather than just change C1?
Also, since I have my GK-1 going right to my lifeforce amps, can I remove the C1 on them too?
Thanks
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Kyrill,
You are right sonically. Deleting C1 will improve the sound. BUT, a teflon will be so close that there's not much in it. :duh:
You are uncompromising, and I am conservative. Respectively, that means no cap, and CAP! I really do urge anyone using a GK1 to have an input cap, it's very good insurance and enhances reliability.
How about this? If you want the best possible sonics, it would be more appropriate to keep C1 on the GK1, use a teflon, and dispense with the output cap on the source (CD/DVD/Tuner), which is usually a very ordinary, very downmarket, electrolytic!! :thumb:
Cheers,
Hugh
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Dear Hugh that is exactly what i am advocating:
"a dedicated C1 cap makes the function of the output cap prior to to the C1 useless
so remove it as it will (serious) degrade the sound unless it is also a hugely expensive film teflon cap but will still sound less than a straight wire"
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oh.
I think Hugh and I thought you were saying to get rid of the C1 on the GK-1m, not the output cap on my sources.
I agree that it makes the most sense, now for a silly question, will the output cap on my sources be easy to identify?
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99% yes
mostly it is the first component the signal path connects to WHEN you follow the wire from the rca output plug to the pcb
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:duh:
That shouldn't be too hard at all :thumb:
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Hey West,
How did you and I so completely misunderstand Kyrill?? :oops:
I sit, resplendent at my glowing keyboard, corrected. :duh:
Kyrill, go to the top of the class. There, you have the floor!! :banana piano:
Thanks,
Hugh
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A dedicated C1 cap makes the function of the output cap prior to to the C1 useless
so remove it as it will (serious) degrade the sound
I'm not sure how he could have said it any better. Thats me -> :bowdown: :thankyou: <- Thats Kyrill
Looks like I need to pay more attention...hopefully I won't be this silly when I'm using the soldering iron (or my table saw). :lol:
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Help help
so top up
i dont get air..
no oxygen
scrggrphmg hurcc errh hurcc srccgr noO0 aii r
plz drag me down
to the floor
to the common laymen's floor
i needdd floor aarrghh
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Kyrill,
Clever students MUST go to the top of the class. Glaring publicity is the punishment for professional success. You are not permitted to sit sullenly in the corner with a funny hat. I can only apologise for not seeing your arguments more clearly before! :duh:
You must get used to the high altitude. I include this amusing story for our mutual delectation, and to make you realise your new position:
A turkey was chatting with a bull.
'I would love to be able to get to the top of that tree' sighed the turkey, 'but I haven't got the energy.'
'Well, why don't you nibble on some of my droppings?' replied the bull. They're packed with nutrients.'
The turkey pecked at a lump of dung, and found it actually gave him enough strength to reach the lowest branch of the tree.
The next day, after eating some more dung, he reached the second branch.
Finally after a fourth night, the turkey was proudly perched at the top of the tree.
He was promptly spotted by a farmer, who shot him dead from the tree.
Moral of the story:
Bull Sh*t might get you to the top, but it won't keep you there..
There are moments when I'm sure this applies to all of us........ :lol:
Cheers,
Hugh
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:thumb:
moral of the story
Not every farmer rewards a courageous turkey :beer:
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Or, a more topical, cynical view, fame is accompanied by self-sacrifice........ :icon_twisted:
Hugh
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Hi,
There has been a discussion of future upgrade or evolution of the GK-1. Well I must admit the full potential of the GK-1R has not been reached which attest to the shear talent of Hugh's design. I did the modification that Ginger suggested where C4 is switched with the LED. There was also a change in a few resistors value. I also did the Platinum mod. Well the latest mod I just did with only three hours of burn in has improved the GK-1R the most, by conservatively 3 or 4 times better. High, mids and bass are improved twice over. Imaging is three-D. Center image stage has been pushed back to the wall behind the speaker. The mod is not expensive just ugly. I replaced the super e-cap configuration of C4 with a film cap, Solen 47 uF 250V. It is big measuring 1.5” x 2.1”. I also replaced a BG at C7 with the same cap. Just replacing the two caps with these two monsters did it. You have to find space under and along side the board, but it is amazing how film caps will transform the GK-1R sound and sound stage compared to the BGs. I first tried Jantzen Cross-caps but the Solens are better. There are probably other film caps that sound just as good as or even better than the Solen but I am so satisfied. My GK-1R is not enclosed so I can easy expand things. Hope there is room to expand if yours is in a box.
Happy listening,
Philip
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HI Philip,
Many thanks for your fascinating input. This is seminal stuff, dammit, causes me to rethink my approach!!
C4 is a decoupling cap on the current source which supplies the output stage of the SS section. This section uses a current source T4 of 12.5mA to supply the voltage amplifier device, T3. The most critical aspect of a current source is the voltage reference; it must be rock steady, regardless of any ripple or noise on the rail from which it is powered. This is achieved with a split current feed from the rail to ground, R13 and R14 each of 2k2, and an electrolytic cap which is strung between the rail and the junction of these resistors. Any differential noise appearing between base and emitter of T4 will show as highly amplified noise at the collector of T4, which coincidentally is the output of the SS section and had better be very quiet otherwise resolution is lost. Evidently, by using a large value film cap here, noise is further reduced because diff noise is converted by this cap to common mode noise. That is, noise is identical on both the emitter and the base of the CCS transistor. In essence this means that the diff noise at these sensitive nodes is eliminated, and thus the heavy amplification of the transistor cannot produce single ended noise at the output. This all shows as superior detail and imaging. In fact, imaging IS superior detail; it's the cueing information of the space; footfalls, breathing, instrument noise and other spatial information which is very, very quiet and often lost in the mix.
I have a notion, Philip, that a tantalum here might be as good as a filmcap, AND it will be much, much smaller. It needs to be rated to 16VW, and polarity is important; with positive to the top.
C7 is another decoupling cap which removes noise from the diff pair, again reducing noise at the output and thus permitting more detail to be retrieved.
My golly, I designed this with Darl Singh, bless him (you there, Darl??) in 2002, and still there are improvements being extracted by AKSAphiles the world over!!
Thank you Philip, you've made my day.....
Cheers,
Hugh
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This is interesting news to be sure. Fitting film cap at C4 and C7 is off the board, and already have a couple of those. But noise reduction anywhere is important as it lets the music through.
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Great job! I might try tantalums as suggested by Hugh. Any special ones that are preferred?
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Hi,
There has been a discussion of future upgrade or evolution of the GK-1. Well I must admit the full potential of the GK-1R has not been reached which attest to the shear talent of Hugh's design. I did the modification that Ginger suggested where C4 is switched with the LED. There was also a change in a few resistors value. I also did the Platinum mod. Well the latest mod I just did with only three hours of burn in has improved the GK-1R the most, by conservatively 3 or 4 times better. High, mids and bass are improved twice over. Imaging is three-D. Center image stage has been pushed back to the wall behind the speaker. The mod is not expensive just ugly. I replaced the super e-cap configuration of C4 with a film cap, Solen 47 uF 250V. It is big measuring 1.5” x 2.1”. I also replaced a BG at C7 with the same cap. Just replacing the two caps with these two monsters did it. You have to find space under and along side the board, but it is amazing how film caps will transform the GK-1R sound and sound stage compared to the BGs. I first tried Jantzen Cross-caps but the Solens are better. There are probably other film caps that sound just as good as or even better than the Solen but I am so satisfied. My GK-1R is not enclosed so I can easy expand things. Hope there is room to expand if yours is in a box.
Happy listening,
Philip
That's amazing, Philip! :o What gave you the idea of using some film caps here?
Now Solens are not generally regarded as the be-all-and-end-all of caps for speaker crossovers ... so, although you heard they are better sounding than Jantzens, do you think there might be a better sounding film cap for here than Solens?
Regards,
Andy
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to be sure
the c4 and c7 are replaced where the original topology placed the c4 and c7 on the board?
i dont understand the "switch" between C4 and LED. was it a switch in place?
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Hi Jens,
No special ones I can think of; the market is not that diverse. But tantalums should be almost as good as a film cap IN THIS APPLICATION where they are merely cancelling noise, rather than passing musical signal.
Hope this helps, and my sincere thanks to Philip for offering his valuable experience here,
Cheers,
Hugh
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Now Solens are not generally regarded as the be-all-and-end-all of caps for speaker crossovers ... so, although you heard they are better sounding than Jantzens, do you think there might be a better sounding film cap for here than Solens?
Regards,
Andy
I've found the Jantzen better than the Solen in speaker xo's but both are outclassed by the standard white Mundorf M-Cap. I've tried the Supreme's, but not worth the coin IMO for xo's.
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Hi Jens,
No special ones I can think of; the market is not that diverse. But tantalums should be almost as good as a film cap IN THIS APPLICATION where they are merely cancelling noise, rather than passing musical signal.
Hope this helps, and my sincere thanks to Philip for offering his valuable experience here,
Cheers,
Hugh
But, Hugh,
The question to me is:
* you specified C4 and C7 as Hitano electrolytics. That's fair enough, given you can't be expected to try a million different caps in each position in the circuit.
* Ginger? then suggested the GK-1 sounded better if these were, respectively, a "Super-E" pair of BG 'Ns' and a BG 'N'.
* then Philip has decided to substitute Solen film caps ... and it sounds even better! :D
* so why would "brand X" tants sound better? Yes they are smaller and so will fit on the board but, unless you:
a) try several brands of tants to compare their sound, and pick the best, and then
b) compare the best tant against Philip's Solens (I happen to have some ... 'xept they're 47uF/400v)
... I don't see how you can say "some tants would be fine"? :?
Regards,
Andy
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Hi,
Hugh, if the tantalum works that means I have to change my board from ugly to colorful. Aren't the tantalum usually colored in pastel? I don't have any tantalum to compare to the Solens. Can't wait to hear from others on how amazing this change is.
Cheers,
Philip
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Hello
A little note about tantalum capacitors.
Every time I used them they fail after only few years, I remember reading few comments about those cap failure from others guys in the Net.
Maby there is a question of quality but it may worth to do a check with Google about tantalum capacitors failure.
Bye
Gaetan
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Gaetan,
You could be right, and thanks for the post! But the new ones from Kyocera, AVX and Kemet are getting very reliable, as they are widely used in the telecoms industry (cell phones) where long life and compactness is important.
Use them only at half rated voltage. In the GK1, rate to 16VW. And get the polarity correct! Wrong way round and they physically blow up, incredible, like a little fire cracker!
Cheers,
Hugh
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To me the exciting thing is that from a combination of user enthusiasm/experimentation and newer more capable components appearing since Hugh’s (& Dahl’s) design, there are improvements to be had for all of us. It took a while before the Platinum became the C1 cap of choice so as a non-engineer, I may have to sit back for a while till you experts experiment a bit. So come on, times a wasting. :D :D :D
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Andy,
Stranger things have happened..... I'd use a rabbits foot if it improved the sound, and mutter incantations at daybreak in Stonehenge..... the fact is, the psycho-acoustic phenomenon is sufficiently subjective to justify trying everything, and this is one of the reasons I take Philip's suggestion very seriously. My suggestion of a tantalum is based on experience as a feedback shunt cap, where it sounded very good indeed and as you will recall was specified in the GK1 from the outset.
The further advantage of the tantalum is that they are tiny, absolutely tiny, and exhibit extremely wideband characteristics, with very low ESR. That's ideal for cancelling noise. The downside of the larger caps like Solen, Mundorfs et al is their bulk; flying leads must be arranged, and the very size of the cap makes it highly susceptible to RFI and spurious noise. Make it too large, and the benefits are lost, so there are good reasons for going small as possible. The new copolymer caps are worth a look, too, Rubycon make them, and I'm using them already in a new 200W amp called the Aztec which should be ready in about three months.
Kafe Friday at 10?
Philip,
The small size of the tantalums is highly attractive, and saves some awkwardness. How they perform is the moot point. I reckon they will be good, but care must be taken not to run 'em hard, so voltage rating should be 16VW. AVX appear to be the most progressive manufacturer at this stage.
Thanks again,
Hugh
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Thanks Philip ... this sounds like a very interesting mod. An RTX relcap could be worth a try without breaking the bank.
Kyrill, the "ginger mod" consists of:
* Use the LED from L1 in the C4 position.
* In the spot where the LED was [L1], use a cap. [I presume this is where Philip has used the Solen since he's also using the "ginger LED mod".]
* Change R13 to 470 ohm
* Change R14 to 10 kohm.
jules
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Hugh,
Is there any chance that this change (tantalum for C4 & C7) could make its way to the pre-built Swift?
Assuming of course that there is general agreement by those that have tried it that it actually does improve the sonics.
Regards
Mark
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Hi Mark,
Possibly, but I have to be damn sure it betters the original design.
That said, I ALWAYS check these things. And I have a few ideas of my own, nuttin' stands still......
'We pursue a policy of continuous improvement, and make no apology for it, so there...... :deadhorse: :hyper: :banana piano:'
Hugh
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Mark,
Further to Hugh’s comment, there is another bonus from Aspen re improvements. What I love is that later ‘production’ changes can mostly be incorporated at the owners cost on Aspen built (not kit) models as I have done on a couple of occasions to bring my Soraya to the latest spec. As his modification costs appear reasonable and uninflated for this service, it’s a win, win situation for the owner that is way beyond what anyone else appears to offer. What’s more, the warranty is preserved. I only hope he can manage to keep this option going as I am always tempted by the latest and greatest. The only problem I have with it is that he always seems to be able to improve on the unimprovable. :thumb: It’s a beautiful thing though. aa
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Lyn,
I must agree, Hugh and his nature of always being determined to build a better mousetrap often manages to hit the target 100%, the mad logical scientist. Of course it all starts with a sound circuit, then over time the tweakers brigade takes hold and improves it further with sometimes boutique, and sometimes non boutique subbed parts ;), Im always thrown aback by how much "voicing" can further refine a product and having a set of a hundred different music loving ears cant be bad for this process...The Soraya is a beauty, most definately..
Colin
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Folks,
Let me reveal Aspen's secret weapon - it is VYnuhl-addict himself!! :o
I'm proud to say that everything I've come up with in the last 18 months has been tested exhaustively and assessed sonically by Colin. This collaboration has accelerated development by a factor of perhaps four times; he is much younger than I am, and jumping out of his skin with energy. I just sit in a cafe with a pen, and doodle - Colin builds it, assesses it, then I do the pcb and layout design, ship the boards to him, and we confirm our hunches.
Wait until you see the latest 200W amp, the Aztec, this is the range topper, and it will, I think, have profound impact in the high end world. All three stages, input, VAS and output, are radically different to anything out there at present, and Colin's input has been huge, thanks Colin!! :thankyou: At least, that is my hope. More tricks than a monkey on a mile of vine, to quote CJ Baker, famed small block NASCAR builder of the eighties.
Cheers,
Hugh
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OK Colin,
It's obviously up to you, then! aa You need to do the testing of GK-1 C4 & C7 with:
* Solen film cap as per Philip's findings.
* another film cap if in fact a physically smaller one can be found.
* tantalum cap, as per Hugh's "suspicion".
:D Regards,
Andy
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Andy, my good friend,
Where are your manners, Squire? :duh:
Colin does things only when and if he wants to do them!!
Besides, Philip, who is 1 smart man, has great credibility and if he says this works, then it does, I'm quite sure....... :lol:
Ask me, I will give you an answer!! :icon_twisted:
Broach the topic over coffee tomorrow! aa
Cheers,
Hugh
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Andy, my good friend,
Where are your manners, Squire? :duh:
Colin does things only when and if he wants to do them!!
Besides, Philip, who is 1 smart man, has great credibility and if he says this works, then it does, I'm quite sure....... :lol:
Ask me, I will give you an answer!! :icon_twisted:
Broach the topic over coffee tomorrow! aa
Cheers,
Hugh
Hugh, of course Colin does things only when and if he wants to do them. I didn't mean to imply otherwise ... however, from your post about him, I suspect he's the sirta guy who is dead keen to extract the best sonics he can out of his gear and therefore would be interested in trying out what Philip did. :D
And I certainly don't disbelieve Philip ... in fact I think he's a genius for actually trying it out! :D Given that I also have the "Super-E" BG Ns in my GK-1 and Philip has heard that the Solens sound better, it is definitely something I need to get around to when next I attack my GK-1 (for the teflons! aa ).
Yes, see you tomorrow for kafe ... when we can discuss things which shouldn't go into print! :lol:
Regards,
Andy
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Thanks Philip ... this sounds like a very interesting mod. An RTX relcap could be worth a try without breaking the bank.
Kyrill, the "ginger mod" consists of:
* Use the LED from L1 in the C4 position.
* In the spot where the LED was [L1], use a cap. [I presume this is where Philip has used the Solen since he's also using the "ginger LED mod".]
* Change R13 to 470 ohm
* Change R14 to 10 kohm.
jules
Hi Jules
So in this sense C4 has disappeared? or is the sames c4 the "use a cap" on the L1 position and in that position meant at the beginning of this post?
for the rating of the tantalums or any other cap Hugh says: 16VW
what is WW? i thought caps were just mentioned by Volts
like 1uF 200V
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...Wait until you see the latest 200W amp, the Aztec, this is the range topper, and it will, I think, have profound impact in the high end world. All three stages, input, VAS and output, are radically different to anything out there at present, and Colin's input has been huge, thanks Colin!! ...
If you can double the power of the Soraya without losing any of the purity, delicacy and refinement, then ... :notworthy:
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If you can double the power of the Soraya without losing any of the purity, delicacy and refinement, then ... :notworthy:
But Darren,
Do you really need 200w into 8 ohms to power your speakers ... given that you've got a sub and so I suppose have rolled off the low end? :D
Regards,
Andy
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If you can double the power of the Soraya without losing any of the purity, delicacy and refinement, then ... :notworthy:
But Darren,
Do you really need 200w into 8 ohms to power your speakers ... given that you've got a sub and so I suppose have rolled off the low end? :D
Regards,
Andy
I didn't really need the worked V8 I had 20 years ago either ... but I still miss it. :wink:
True, my speakers are an easy load though only 83db or so .... but if I could have double the power without giving anything up ... :drool:
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Hugh, this thread is filled with goodies - great input input from knowledgeable and enthusiastic Aksaphiles :D
Perhaps it would be worth making it a "sticky"?
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I agree with Jens, the info on this thread is for keeps
and I also agree with Darren, the same reason I jump on the 200W AKSA prototype.
Rom
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Folks,
Done, topic merged and subject amended....... thanks Jens, great idea :drool:
It is probably clear now that Aspen is not solely Hugh Dean - there are ten or twenty people out there across the globe who contribute in a myriad of ways; a recent case concerned a Computer Science academic in Bangalore with whom I had a long dialogue about PSpice and distortion analysis. I sent him a circuit, he analysed it with great perception, and identified a possible issue. I went for a jog in the park, returned with an idea, figured out a likely solution to the problem over a cup of good coffee, discussed it with Colin, who built and auditioned it in days, approved it, and voila, a new concept was tested. Then Colin went googling, found that this same solution had been identified in an early Halcro patent, and Siva ran PSpice over it and confirmed that yes, it did have markedly lower levels of odd order distortion.
Philip then implemented the idea, and quickly found that the sonics were markedly improved.
That was a good day, and an extraordinary collaboration. When one thinks on the distances, the communication, and the ideas being tossed around here - this would not have been possible until the advent of the internet, where text, graphics and even living dialogue can be instantly exploited at low cost. These situations are happening much more often now, as my skills, my network, and my collaborators hone our collective abilities. From a purely sociological point of view, this is an extremely interesting time for mankind, and it is also a technical/cultural renaissance in a sense as so many peoples from different parts of the world are able to easily communicate in one common language, bound by a single network protocol - unheard of even a hundred years ago.
Audio is a tiny part of this. Consider the remote surgery now possible using the TCIP technologies, and mechatronics! I can talk to my daughter in NYC on her computer using Skype for around ten times less than I can make a local call to a cell phone here in Melbourne - the world is an amazing place.
Darren, I swear to you that the delicacy and refinement will not be lost, just because the engine has more cylinders...... and the appeal will be just as it was on your worked V8!
Andy, you are right...... tomorrow it is!
Cheers,
Hugh
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...there are ten or twenty people out there across the globe who contribute in a myriad of ways.
...
When one thinks on the distances, the communication, and the ideas being tossed around here - this would not have been possible until the advent of the internet, where text, graphics and even living dialogue can be instantly exploited at low cost.
This has a parallel in the software world - Open Source.
Some say that open source software has the potential for higher quality than corporate developed software exactly because of the collaboration of very clever people from all over the world.
And the bonus for Hugh (and the rest of us) is that many folk will contribute soley for the intellectual challange.
Regards
Mark
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:), sorry kyrill, I didn't make that clear.
Yes, the cap that was in the C4 position [originally a 47uF, 35VW Hitano] is moved to the L1 position and the LED that was in the L1 position is moved to the C4 position.
jules
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Kyrill, Jules,
The C4 mod is merely another way of doing a current source, and it relates to removing all noise from the voltage reference, the LED. There are a few ways this can be done; I use a bootstrapped current feed to the LED, enabling a cap to deliver common mode noise at both ends of the LED, thus cancelling noise at the reference. Ginger's technique is to run a small resistor from LED reference point to the base of the CCS device, then string a cap from the base to the rail, decoupling it from the LED. I've built and tested both, and for me the existing design worked best, but others disagree. If this works for you, and it clearly does for Ginger, use it. I have a strong preference for my technique because it uses a smaller cap rated to higher voltage; Ginger's design uses a large cap rated at very low voltage. I think both current sources are extremely effective, and very quiet, but design of CCS blocks is a science in itself, with lots of very sophisticated designs available. One must keep it simple, of course.
Cheers,
Hugh
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Thanks Hugh ...
:oops:, I seem to have done a very bad job of explaining a very simple mod. While the positions are exchanged the original cap is replaced by a Black Gate, 6.3V, 22uF if my records are correct. There's also the super E configuration that Andy mentions rbut I don't think I'll go there after having fumbled my way through this one :D
jules
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Andyr,
I must say I really like the Solen Mkp-FC630v, they have their place though and sized carefully can sound absolutely beautiful, I use them for Ac coupling and by being too generous with value in this role can turn the highs to mud easily ;). I would try these mods in the Gk-1 if I owned one, currently working on that issue as I can tell its a real stellar preamp. As Hugh stated yes I do things when I want to, which is most of the time the hardest part for myself is being able to walk away from a sonic mission, haha. Oh yes, and a bypassed Solen in shunt mode on the Woofer X-over sounds much better than a single Solen, not the same story on tweeters.
Hugh,
Thank you profusely for your very kind words, your the easiest person to work with and its always an exciting adventure wiring these ideas up,testing, and rolling those parts to and fro, the internet has been an indispensable line a communication most definately. Im VERY excited about the Aztec, I guarantee many surprises in sonics, its utterly transparent and music just flows with absolute grace with an incredible soundstage, the sad part is having to kick the musicians out night after night ;)..
Now time for some more music!
Colin
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thx for the explano, no c4 mod for me :)
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Hi Jules,
No problem. This is NOT an easy mod to explain, don't beat up on yourself. Thank you for taking the trouble, in fact.
I hope Ginger is not upset by my comments; I do know a very clever Texan engineer who agrees with him, it's just my POV, and might well be wrong.....
Cheers,
Hugh
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Hi,
There has been a discussion of future upgrade or evolution of the GK-1. Well I must admit the full potential of the GK-1R has not been reached which attest to the shear talent of Hugh's design. I did the modification that Ginger suggested where C4 is switched with the LED. There was also a change in a few resistors value. I also did the Platinum mod. Well the latest mod I just did with only three hours of burn in has improved the GK-1R the most, by conservatively 3 or 4 times better. High, mids and bass are improved twice over. Imaging is three-D. Center image stage has been pushed back to the wall behind the speaker. The mod is not expensive just ugly. I replaced the super e-cap configuration of C4 with a film cap, Solen 47 uF 250V. It is big measuring 1.5” x 2.1”. I also replaced a BG at C7 with the same cap. Just replacing the two caps with these two monsters did it. You have to find space under and along side the board, but it is amazing how film caps will transform the GK-1R sound and sound stage compared to the BGs. I first tried Jantzen Cross-caps but the Solens are better. There are probably other film caps that sound just as good as or even better than the Solen but I am so satisfied. My GK-1R is not enclosed so I can easy expand things. Hope there is room to expand if yours is in a box.
Happy listening,
Philip
This got my attention upon initial posting. However film caps at the 2 positions are just not in the cards. Thus I thought I'd give the tantalum caps a go, the expensive AVX ones no less.
Well, all I can report is that the tantalums really offer not much difference to the previous caps, Rubycon ZA at C4 and Sanyo OsCon at C7. However, since I was working on the GK-1 I decided to take out the output cap, in my instance a 1uf Mundorf Silver/Oil, and just replace it with a wire link. The Platinum on the input of the LF should take care of anything, so seemed safe to do this. This seemed to make a small improvement, but not too much really.
However, if you really want to get serious about noise reduction and an increase in music.................................. ..................
Modify your cd player with a fancy aftermarket clock and power supply. I recently did this on my Marantz player. The noise floor dropped towards the center of the earth and all this music emerged with new clarity. ALL the veils that people so commonly refer to are removed.
Here are some links to research:
www.tentlabs.com
www.newclassD.com
www.audiocom.co.uk
If you can do the work yourself, can be done for as little as a 200USD. If it's done elsewhere, figure on 500USD and up.
Steve
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Well, all I can report is that the tantalums really offer not much difference to the previous caps, Rubycon ZA at C4 and Sanyo OsCon at C7.
Steve
Mebbe you have to wait a long time for the tants to run in?
Regards,
Andy
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Hi Philip, Steve,
Many, many thanks..... this is real inneresting..... We move closer to open source high end with each month now!!
The Ginger mod replaces a bootstrapped voltage reference with a conventionally decoupled voltage reference. Until the solen was added I believe both were very similar sonically. Is that true?
The replacement of C7, which is the final cap standing sentry over current delivery to the long tailed pair of the SS section, seems to have been a revelation. A good filmcap there makes a big difference, it seems. This is for noise reasons, I would say; that cap filters the last shred of noise from the current which powers the input stage.
Replacing a premium Mundorf with a wire brings only a marginal improvement, it seems. That's a great flattery to the Mundorf, I have to say, and yes, if the amp follower has a teflon input cap (in this case rated to 400 thumping volts!!) it's fair to say this is a prophylactic so heavy duty.... (I guess I better leave this one alone.....!!) The amp should survive a mid-west twister in this scenario, so Kyrill, do please go ahead and delete the GK1 output cap!!
This is all good stuff, and my sincere thanks go out to the experimenters. This is a rich, rich resource, thank you sincerely,
Hugh
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Given the placement of C7 on the board, in the middle of everything, it's pretty difficult to have anything but a small cap there.
There's a little more to my story however.
When I swapped in the tants and wanted to replace the Mundorf's, I first decided to reinstall the auricap w/rtx bypass. My first impressions here were mixed. I slept on it overnight pondering just going with a wire link. A listen yesterday morning was the decider as I didn't think things sounded as good as before. After installing the wire link, everything all better.
So, I suppose this just confuses everything in a way.
Nevertheless, noise reduction with a clock and power supply is not a subtle improvement, it is MAJOR.
But of course, that comes in the realm of The Beyond here.
Steve
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Re: Space requirements for C4 and C7 replacements.
The replacement of C4 and C7 seems to be the ideal application for the new WIMA MKS-2XL film caps.
There's a 22uf 16V MKS 2XL 5% with 5mm lead pitch available, though I've not seen any in the flesh yet.
Two of these in parallel should do the trick, they could even be a direct replacement for the Super-E BGs?
Minimum order quantities for these babies are in the hundreds at the moment, so if anyone knows where to get a handful to try, please let me know.
Cheers,
Ron.
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Re: Space requirements for C4 and C7 replacements.
The replacement of C4 and C7 seems to be the ideal application for the new WIMA MKS-2XL film caps.
There's a 22uf 16V MKS 2XL 5% with 5mm lead pitch available, though I've not seen any in the flesh yet.
Two of these in parallel should do the trick, they could even be a direct replacement for the Super-E BGs?
Minimum order quantities for these babies are in the hundreds at the moment, so if anyone knows where to get a handful to try, please let me know.
Cheers,
Ron.
Indeed they do seem like a great candidate ... seeing as how Steve has experimented with some tantalums and found they don't deliver the kind of improvement which Philip achieved with his Solens (which do present problems in terms of their size and requirement for flying leads! :( )
Can someone find a small-quantity supplier?? :D
Regards,
Andy
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Hi Ron,
I was not aware that Wima had done a low voltage MKS - thank you for letting us know!! Years ago Philips used to do a block MKS in 100V, but until now that was the lowest filmcap voltage I'd seen in the >10uF range.
In truth, a single 22uF should do the trick here. I used 47uF electros because they are small, but a film cap may be more effective at lower capacitance so give it a try.
Cheers,
Hugh
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My comments about the tantalum caps need to be taken in the proper context. The improvement I gained with realizing low single digit jitter and resultant large drop in the sound floor may be much more than any noise reduction gained by the tantalum caps.
-
I replaced the super e-cap configuration of C4 with a film cap, Solen 47 uF 250V. It is big measuring 1.5” x 2.1”. I also replaced a BG at C7 with the same cap.
Hi Philip,
Did you twist the pair of wires to each Solen? (I believe this reduces pickup of noise?)
Regards,
Andy
-
This got my attention upon initial posting. However film caps at the 2 positions are just not in the cards. Thus I thought I'd give the tantalum caps a go, the expensive AVX ones no less.
Well, all I can report is that the tantalums really offer not much difference to the previous caps, Rubycon ZA at C4 and Sanyo OsCon at C7. [ ]However, since I was working on the GK-1 I decided to take out the output cap,in my instance a 1uf Mundorf Silver/Oil, and just replace it with a wire link. The Platinum on the input of the LF should take care of anything, so seemed safe to do this. This seemed to make a small improvement, but not too much really.
However, if you really want to get serious about noise reduction and an increase in music.................................. ..................
Modify your cd player with a fancy aftermarket clock and power supply. I recently did this on my Marantz player. The noise floor dropped towards the center of the earth and all this music emerged with new clarity. ALL the veils that people so commonly refer to are removed.
Here are some links to research:
www.tentlabs.com
www.newclassD.com
www.audiocom.co.uk
If you can do the work yourself, can be done for as little as a 200USD. If it's done elsewhere, figure on 500USD and up.
Steve
Hi Steve
I "dared" some time ago to delete caps in the input or output signal between source all the way up to poweramps, having your line of reasoning. However in the case of the GK1 you do something that i do not dare. I hold on to the output cap of the Gk1 and remove the input cap of the power amp.
without outputcap the GK-1 delivers ( if i understand Hugh right) 40V DC, so it introduces relatively high voltages on the IC. If ever the Gk1 this way is connected to another device with removed caps disaster in the amp next to the tweeters are surely to happen.
normally caps ( unless with tube sources/preamps) removed, pass thru DC between 100mV-2V
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Hi Steve
I "dared" some time ago to delete caps in the input or output signal between source all the way up to poweramps, having your line of reasoning. However in the case of the GK1 you do something that i do not dare. I hold on to the output cap of the Gk1 and remove the input cap of the power amp.
without outputcap the GK-1 delivers ( if i understand Hugh right) 40V DC, so it introduces relatively high voltages on the IC. If ever the Gk1 this way is connected to another device with removed caps disaster in the amp next to the tweeters are surely to happen.
normally caps ( unless with tube sources/preamps) removed, pass thru DC between 100mV-2V
I could switch my Platinum caps around a bit, but I can't really be bothered. I don't think anything is going anywhere else for some time.
Steve
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OK you guys,
winter is approaching in OZ, which means longer nights and more time over the soldering table :)
But trying to follow all the mods which sound so worthwhile is certainly confusing, going back and forward all the emails is giving me vertigo.
For those of us who are daring but do not have the electronic know how, we would be greatly helped by some sort of road map about what to do.
A sort of mod guide with
basic mod
middle mod
advanced mod
and "if you dare mod straight wires and all" specifying brand , type( film etc cap) and value range/size to make sourcing easier.
This would systematically document once and for all the great changes done to this beaut pre amp. It would be time consuming to compile but a very valuable resource.
The same could be said about the LF mods.
Anyone? :surrender:
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Hi Andy,
I did not twist the lead wire to the Solen caps. I used 18 gauge teflon coated wire as leads to help support the heavy caps and tried to use the shortest leads as possible. I have no problem with hum with the addition of the large caps.
When I return from vacation, I will try to determine the relative contribution of C4 and C7 to the improvement. I first changed C4 on one channel and noticed a huge improvement in the high and when I changed the other channel I changed C4 and both C7 to Solens. I think the C4 change contributes the majority of the improvement but only with both channel changed did I notice the bass improvement.
Cheers,
Philip
-
the value of C4 and C7 are the same same as in the building manual ( except Hugh's suggestion "In truth, a single 22uF should do the trick here. I used 47uF electros..."?
-
OK you guys,
winter is approaching in OZ, which means longer nights and more time over the soldering table :)
But trying to follow all the mods which sound so worthwhile is certainly confusing, going back and forward all the emails is giving me vertigo.
For those of us who are daring but do not have the electronic know how, we would be greatly helped by some sort of road map about what to do.
A sort of mod guide with
basic mod
middle mod
advanced mod
and "if you dare mod straight wires and all" specifying brand , type( film etc cap) and value range/size to make sourcing easier.
This would systematically document once and for all the great changes done to this beaut pre amp. It would be time consuming to compile but a very valuable resource.
The same could be said about the LF mods.
Anyone? :surrender:
Geraldo,
All you really need to know and do is:
1. .47uf teflon cap at C1 Most use Sonic Cap Platinum. Install off the pcb in place of signal input wire.
2. .01uf teflon cap at C19. Small size and can be interchanged with the stock cap.
3. Tubes: This is pretty subjective to the listener. I like the NOS 7308's, though they are a little expensive. Stock tubes are fine. NOS 6es8's may bring a small improvement. Again, it's pretty subjective.
Anything else that has been described in these pages is extra. You may hear some benefit, you may not. I've changed most every cap in the whole GK-1, and only the above 2 provided any clear improvement that was easy to hear.
Steve
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The C4 & C7 mod, using film caps [I read Hugh's view as suggesting that 22uF is acceptable too kyrill] apparently works to reduce "differential noise".
I'm wondering what the source of this noise is. Is this internal to the amp or are we talking about something produced by the grid power supply? It seems that the power supply in many parts of the world can be a real problem. The US system with its lower voltage seems to be particularly susceptible to contamination, as do buildings with poor wiring.
Philip ... What's your home power supply like and have you done the C1 teflon mod.?
jules
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The replacement of C4 and C7 seems to be the ideal application for the new WIMA MKS-2XL film caps.
Can someone find a small-quantity supplier?? :D
I can only find 1 supplier that has these in stock (10% version), TAW Electronics in the US.
There are not many left, and they're 11 USD each!
Hopefully the price will go down as they become more common.
Also, for those "In the trade", WIMA will send out small quantities as samples.
Cheers,
Ron.
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"there are not many left.."
they sell by single pieces..?
-
I can only find 1 supplier that has these in stock (10% version), TAW Electronics in the US.
There are not many left, and they're 11 USD each!
Hopefully the price will go down as they become more common.
Cheers,
Ron.
Mmmm, the only problem with buying +/-10% value items is that you probably need to buy at least 10 of them to get a statistically likely chance of getting 2 values within a few % of each other. :( (IMO, getting 2 values 10% apart is just too much.)
Regards,
Andy
-
it completely depends on the application?
-
OK you guys,
winter is approaching in OZ, which means longer nights and more time over the soldering table :)
But trying to follow all the mods which sound so worthwhile is certainly confusing, going back and forward all the emails is giving me vertigo.
For those of us who are daring but do not have the electronic know how, we would be greatly helped by some sort of road map about what to do.
A sort of mod guide with
basic mod
middle mod
advanced mod
and "if you dare mod straight wires and all" specifying brand , type( film etc cap) and value range/size to make sourcing easier.
This would systematically document once and for all the great changes done to this beaut pre amp. It would be time consuming to compile but a very valuable resource.
The same could be said about the LF mods.
Anyone? :surrender:
Geraldo,
All you really need to know and do is:
1. .47uf teflon cap at C1 Most use Sonic Cap Platinum. Install off the pcb in place of signal input wire.
2. .01uf teflon cap at C19. Small size and can be interchanged with the stock cap.
3. Tubes: This is pretty subjective to the listener. I like the NOS 7308's, though they are a little expensive. Stock tubes are fine. NOS 6es8's may bring a small improvement. Again, it's pretty subjective.
Anything else that has been described in these pages is extra. You may hear some benefit, you may not. I've changed most every cap in the whole GK-1, and only the above 2 provided any clear improvement that was easy to hear.
Steve
Steve--
Thanks for your posting summarizing the cap changes. I recall reading posts (not necessarily yours) from several months ago that changing from the supplied potentiometer to a stepped attenuator (such as the TKD) can yield a noticeable improvement. I don't recall anyone concluding later that a stepped attenuator is NOT a worthwhile upgrade. In addition to the recommended cap changes, and maybe some tube rolling, do you think a stepped attenuator is a worthwhile upgrade as well? If it is, I want to allow room for it in the final layout and chassis I construct, now that I'm getting to that point.
Mark
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Steve,
I hope I'm not jumping in here,
apart from the stepped attenuator which I thought made a noticeable difference(and I only used a 60dollar one), some have also found that if you use both the sub out and the tubes out, a buffer also makes big difference. I do not understand the technical reasons for this other than if you use a powered sub its a must.
Andy you know more..
-
Hi Theo,
Andy, would you care to add your comments here? With some qualification, I agree with Theo,
Cheers,
Hugh
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Gentlemen,
Yes, with Hugh's assistance, I created an op-amp buffer circuit to go between the wiper of the volume control and the "Sub Out" RCAs, because I needed to be able to drive 35' interconnects (between my GK-1 and active XOs, as I use Sub Out to drive the bass LP section of my active XOs - and I get more bass punch as a result, compared to driving the bass from the normal tube output stage).
However, this buffer circuit turned out to have an unexpected benefit ... it made the bass from the Sub Out go deeper! aa BTW, this wasn't revealed on my own system - I had lent my GK-1 to "SuperMart", who was running a sub with his AKSonics, and he just substituted my GK-1 for his Swift.
A "naive" explanation is that, when you connect a sub to the volume wiper, the bass signal from "Sub Out" is somewhat degraded, depending on how far you have the volume turned round. Putting a buffer here (just as there's a "tube buffer" on the "normal output") means the signal is no longer degraded. So I recommend it! :D
Regards,
Andy
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"degraded"?
I would expect the output impedance is changing in accord with the position of the wiper.
to high an output relative to the input of the sub amp less bass and so on.not only less bass, also less dynamics. that is therefore i like the output impedance to be less than 100 and or the input impedance at least 47k better 100+k
-
Andy,
when I connect the sub out, the tube out signal is degraded. The tube sound goes flat and looses all the top end. I have a vague recollection that Hugh had a reason for this, I think? I am not sure if the buffer fixes this issue as well?
Theo
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Hello all,
Two new subjects have come up, and I can only add my own experiences to the body of experiences/observations.
I use a shunt stepped attenuator with fancy resistors. Can't say I really have done any comparing to anything else. The stock cermet attenuator is a good one, but if you allow some space behind the front plate you can always use attenuators now or later.
I run a sub out after the volume attenuator. I have a short run to a sub. I don't need a buffer. There is no sound degradation to the buffered tube output. Hugh and Marty have heard my GK-1 in Marty's system.
Steve
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Andy,
when I connect the sub out, the tube out signal is degraded. The tube sound goes flat and looses all the top end. I have a vague recollection that Hugh had a reason for this, I think? I am not sure if the buffer fixes this issue as well?
Theo
Aah, that's interesting to know! :o I'm certain the Sub Out buffer fixes this problem too ... after all, did you notice "flat sound with no top end" at my place the other night? :lol:
However, the maestro will need to confirm this.
Regards,
Andy
-
Interesting stuff ...
I'm wondering how a Burson Buffer might fit in with this sub matter. The usual placement for these is before the pre-amp [or in the pre-amp if you can manage it :)]. The BB gives a 6 db gain which could be very useful here. It's also possible to order them with a higher gain though I'm slightly doubtful about this path. I use a BB myself and it's one of the best additions I've made to my system but I don't have a sub in there yet so maybe someone else can comment.
Another option for the sub would be to have the sub amp separate from the sub itself and right next to the rest of your amps/preamps etc. I'm surprised this isn't done more often as it has the logic of reducing the length of a signal interconnects by increasing the length of the "speaker" wires. It also gets the sub amp away from the vibrations of the sub but this might not be significant. This change wouldn't help if the problem is that the sub somehow steals part of the signal to the rest of the system.
On attenuators ... I believe the TDKs have become very expensive lately. There are several DIY options for those who want to practice their soldering. I've used a full ladder Elma [from Percy Audio] and these have the advantage of using only one resistor per channel at any level you have them set.
Space is always a good idea whatever you happen to be doing, so yes, leave some space for an attenuator and leave some more space to help avoid problems with fields surrounding various bits of wiring.
jules
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There has been talk in the past about changing cap values to affect the system f3. can anyone comment on where this would lie with the suggested C1, C19, C21 changes?
cheers
Nick
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I'm surprised this isn't done more often as it has the logic of reducing the length of a signal interconnects by increasing the length of the "speaker" wires.
IMO there is no "logic" in reducing the length of signal ICs, so as to increase the length of spkr cables.
With ICs, there's bugger-all current flowing, so L and R are irrelevant; C is the only parameter which can affect the sound ... apart from the dielectric around the copper/silver wire. The amount of C which is acceptable depends on the ratio of the Zout (output impedance of your source/preamp) to Zin of your power amp. If you have a ratio of 100+ (my own is about x350) you can have quite high C (read "long ICs") without any sonic detriment. :-))
Spkr cables OTOH carry large currents - so low:
* R is important, otherwise the resistance of the cable relative to the driver impedance becomes too high for the amp to be able to exert the best control over the driver, and
* L is important, as it acts as a "brake" against changes in current flow.
Dielectric behaviour is also important (whereas C is only important to the power amp driving the spkr cables).
Achieving low R and L with spkr cables is a much more dificult exercise to get right than just low C on an interconnect.
Regards,
Andy
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Andy
.. Achieving low R and L with spkr cables is a much more dificult exercise to get right than just low C on an interconnect. ..
wouldn't it make sense to minimise therefore the length of the SC at the "expense" of longer ICs?
so have 2x mono poweramps
-
Andy
.. Achieving low R and L with spkr cables is a much more dificult exercise to get right than just low C on an interconnect. ..
wouldn't it make sense to minimise therefore the length of the SC at the "expense" of longer ICs?
so have 2x mono poweramps
Absolutely! :D
My own spkr cables are 200mm long! :o
Regards,
Andy
PS: In my case it's 6x mono poweramps! :D
-
Andyr
with such short lenghts, can you discern differences between different brands/self made cables?
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[/quote]
Aah, that's interesting to know! :o I'm certain the Sub Out buffer fixes this problem too ... after all, did you notice "flat sound with no top end" at my place the other night? :lol:
However, the maestro will need to confirm this.
Regards,
Andy
[/quote]
Andy,
Absolutely not.
However you are not running a powered sub off the sub out of the GK. You are running the sub out of the GK into a lifeforce into to base panels. I do not know if that actually makes a difference with impedance matching?
theo
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Andy,
Absolutely not.
However you are not running a powered sub off the sub out of the GK. You are running the sub out of the GK into a lifeforce into to base panels. I do not know if that actually makes a difference with impedance matching?
theo
No, I'm not running a sub ... and the Zin of my bass XO is 100K, which is probably a lot higher than many sub plate amps. So mebbe you're correct ... "Sub Out" is affected with some (very low) Sub plate amp Zins?
If you heard a degraded tube out signal when you connected your sub then what Zin is its plate amp?
Regards,
Andy
-
The sub-out feature of the GK1 was a consequence of an unusual attenuation topology. Let me explain according to my understanding of this important component.
Level controls, in potentiometer (three terminal) form, ideally require two parameters for best sonics. One is a low source impedance to drive the pot, otherwise attenuation is highly variable with the source chosen; and the second is an extremely high target impedance for the circuit block being driven from the wiper.
The problem is the wiper. At the point where it slides on the carbon/plastic track, there is spring pressure, and this means that the wiper contacts the track, distorting it physically at a number of microscopic points, setting up a small number of alternate paths into the circular resistive substrate. These multiple paths will be pretty much at the same voltage if no current is flowing, but if a current is flowing into the wiper, then they will all differ in their voltage drops and the output will tend to jarble the sonics. The only way to avoid this problem is to draw no current through the wiper, and this mandates a very high target impedance.
Thinking on this, I felt that since we could not control the source impedance driving the preamp (digital and tube sources are different, as you'd expect), and since the input impedance into the GK1 was around 45K, fixed by the input stage topology, it might be better to place the volume control between the SS and tube sections. The Zout of the SS sections is around 30R, nice and low, and the Zin of the tube stage, with its bootstrapped, self biased cathode follower, is 4.3M (calculated), extremely high. This would mean that the SS section operates at full line level, but the tube operates only at the listening level set by the volume control.
This 'enclosed' environment thus defines the ideal point for a level control. Source and target impedances are optimally controlled, and almost no current flows from the wiper into the tube grid.
However, if we connect a sub amp to the wiper, then it must deliver a small current into the amp input via the wiper contact, blurring the waveforms as described above. This is the problem, and it flattens the sonics for the tube.
The only way around this is to insert a buffer, an opamp of good quality is fine, between the wiper output (sub-out) and the sub woofer amp. Andy has done this to good effect. This prevents the sonic effect on the tube output, as Gerado has noted, by restoring the wiper current to negligible levels.
It's worth noting, too, that the gain of the tube is around 0.92, that is, 1Vrms in will yield 0.92Vrms out, and if we take the sub-out at the 1Vrms point you can see that the bass frequencies will enjoy a small lift. It's very low, however, around 0.72dB, and I doubt most would hear it, (1.5dB is acknowledged to be around the finest resolution of the human ear), but it's nice to have it......
Hope this is helpful,
Cheers,
Hugh
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Ah ha ... most helpful, thank you Hugh
Andy, a small point of order:
IMO there is no "logic" in reducing the length of signal ICs, so as to increase the length of spkr cables.
I agree completely. My post was badly worded. It would be very silly to have long SCs as a goal. :D
jules
-
Hi all,
I don't want to start an off-topic debate, but there are several people whose opinions direclty contradict Andy's (I would hate for someone to spend $$$ on modding their system without being exposed to a cross-section of views). This is directly from Mapleshade audio's website:
NEVER use speaker cables shorter than 8'. Amazingly, 4' sounds much worse than 8'. Contrary to common belief, shorter interconnects (2 m or less) and longer speaker cables sound WAY BETTER than the opposite—based on extensive head-to-head tests.
http://www.mapleshaderecords.com/audioproducts/freeaudiotips.php (http://www.mapleshaderecords.com/audioproducts/freeaudiotips.php)
I don't have an experienced-based view, so I will say no more.
-
This is directly from Mapleshade audio's website:
NEVER use speaker cables shorter than 8'. Amazingly, 4' sounds much worse than 8'. Contrary to common belief, shorter interconnects (2 m or less) and longer speaker cables sound WAY BETTER than the opposite—based on extensive head-to-head tests.
But marcus, where does that leave all us ATC/Orion/etc. active speaker owners? Fer shure there ain't 8' of cable per driver coiled up inside each active ATC speaker box! :scratch:
Regards,
Andy
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Amazingly, 4' sounds much worse than 8'.
I just don't see how this is any way possible. It just doesn't make any sense. There must have been another factor here.
Contrary to common belief, shorter interconnects (2 m or less) and longer speaker cables sound WAY BETTER than the opposite—based on extensive head-to-head tests.
This however, seems like it COULD make sense...
I don't have anything new to add, but I just don't see how 4' can sound any better than 8'
-West
-
Re Speaker cable lengths:
Most amplifiers need to 'see' some inductance on their outputs. Some manufacturers (e.g. Naim) provide this by using inductive cable (NAC A5), which means that the inductance is proportional to the length of the cable! I think the accepted best sounding length for a Naim 250 / NAC A5 combination is around 3-4 Metres.
So longer cables can sound better than short cables. :scratch:
Hugh's designs include a wound inductor on the output already, so they are much less dependant on the cable inductance (but it still has some effect).
Cheers,
Ron
-
I have read somewhere in the distant past, someone suggesting that the assumed-ideal of zero resistance & reactance for a speaker cable is in fact an error of judgement because it in turn assumes a perfect amp (performance independent on load reactances) and a perfect speaker (presumably totally resistive => non resonant and frequency independent). In a real world, the compex load characteristics of drivers interact in a nasty way with global negative feedback amps. The hypothesis is that having some degree of "electrical separation" can actually benefit the amplifier/speaker interface. Bollocks? :scratch: Who knows...?
Back on topic, has anyone tried to repeat Philip's experience with Solens or other large film caps? Seems there's been a lot of talk about tantalums, small WIMA films, etc, but I don't recall anyone giving Philip's specific mod a go?
-
I have read somewhere in the distant past, someone suggesting that the assumed-ideal of zero resistance & reactance for a speaker cable is in fact an error of judgement because it in turn assumes a perfect amp (performance independent on load reactances) and a perfect speaker (presumably totally resistive => non resonant and frequency independent). In a real world, the compex load characteristics of drivers interact in a nasty way with global negative feedback amps. The hypothesis is that having some degree of "electrical separation" can actually benefit the amplifier/speaker interface. Bollocks? :scratch: Who knows...?
I suggest this proposition is relevant to "conventional" passive-XO speakers ... not (active) situations where the same amp is connected to just one driver? I say this because IMO, the inductive load which a passive XO presents to an amp is more complex than that offered by a driver (whose reactance can be corrected anyway by a Zobel, if need be) ?
Regards,
Andy
-
Re Speaker cable lengths:
Most amplifiers need to 'see' some inductance on their outputs. Some manufacturers (e.g. Naim) provide this by using inductive cable (NAC A5), which means that the inductance is proportional to the length of the cable! I think the accepted best sounding length for a Naim 250 / NAC A5 combination is around 3-4 Metres.
So longer cables can sound better than short cables. :scratch:
Hugh's designs include a wound inductor on the output already, so they are much less dependant on the cable inductance (but it still has some effect).
Cheers,
Ron
I guess I stand somewhat corrected. However, I did think that was a possible explanation, but the difference of inductance in a 4' to 8' would not be that big of a change from the amps point of view, no?
Also, I think we should try and get back to the Gk-1 as we have slowly drifted away.
-
I suspect you're right Andy, but in a genuine attempt to kill off-topic conversation, I won't comment further.
If any Aussie's want to try Solens at C4 & C7 and would like to ammortise international postage across a small group buy, PM me. I am curious enough to give it a go (I am much more of a "capacitor believer" than a "wire believer" anyways).
-
i would be interested in the group buy too too but give it a go and start a new thread "calling" GK-1 owners to come forward. It would be silly to go all the way for a GK-1 and then react lukewarm to cold to this mod
-
Hi,
I just finished placing the large Solen caps at only the repositioned C4 location on a Gk-1R that I built for my son. I have yet to give it to him, but right now I’m using it in my workshop system. This is a very simple system with a bottom of the line Sony DVD-Cd player with the smallest Paradigm bookshelf speakers powered by a LF50. The Solen caps look like outboard fuel tanks on the wing tips of a plane. I was initially afraid that what I heard on my Orion system with the Solen caps was mainly due to the other upgraded components.
Nope and the good news is that the C4 is the most important cap position. I can safely say that the GK-1R sound is twice as good, now with these large caps. Yes this GK-1R has the platinum caps at C1 and C19. C21 is stock. What is twice as good? Well the pianist is twice as good and the drummer has twice as many cymbals. Bass is also better from these small speakers. Imaging is amazing for the bookshelf position. Well I’m very pleased with only the C4 caps replaced. Happy listening.
Cheers,
Philip
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I just finished placing the large Solen caps at only the repositioned C4 location on a Gk-1R that I built for my son.
"Greater love hath no man that he should build a GK-1 for his son"!! :lol:
I really don't think mine would appreciate it ... he's firmly of the "iPod with earbuds" generation! :D
Regards,
Andy
-
Next time I visit, Andy, I'm going to have a word with your son. He needs some character guidance, I can see.
Phil,
Many thanks for your post, seminal information. Can you please send me a short test email, I'm having real problems connecting with you......
Cheers,
Hugh
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o dear Hugh :notworthy:
I have 2.5 sons. 2 of myself one is me nephew son of my best friend and neighbor. Der nephew is 4 weeks older than my youngest .ALL of them are iphone earpod lovers and prefer mp3 over flac
Can i send them to you? as a return favor you hold them in yr workplace alias labour camp and learn them how to solder, clean the ground, do your admin, count yr inventory and call you 'master"
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O Kyrill,
I would like that, can they call me Bwana??
I'm not quite 84 yet, but I'm getting there.......
Cheers,
Hugh
-
"Young Bwana"
then :wink:
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kyrill,
I think a group buy might be the way to go here. Since there are some of us state side, I would be willing to order them, then distribute to those in the us, then ship one box down under, where one of you could distribute the rest.
http://www.mouser.com/Search/ProductDetail.aspx?qs=QkNLLRillGlAv7CRXI%2fxIQ%3d%3d (http://www.mouser.com/Search/ProductDetail.aspx?qs=QkNLLRillGlAv7CRXI%2fxIQ%3d%3d)
We would need 17 people to buy 8 of them, or 14 people to buy 10. Basically we need to hit the 135 mark if a group buy is going to work, but if we get close enough, I might be willing to pick up the slack, and then have some extra caps incase someone comes in late into the buy. Also, the factory lead time is 12 weeks!
The only problem is that I have no way to match capacitors, and therefore I could not ensure that all four would be close in value to those who are state side.
-West
p.s. If there is a cheap capacitor tester that I can build, or buy, I might be interested in picking that up to help this group by, and future projects.
-
My Wima 22uF MKS2-XL caps have just arrived in the post.
I got 2 good matched pairs from 6 Caps, so I'll attack C4, then C7.
Unfortunately, modding won't be possible until the weekend, but I'll post my first impressions then. I also have a couple of 20uF Solens to compare them with, but this will take a bit longer....
Cheers,
Ron.
-
My Wima 22uF MKS2-XL caps have just arrived in the post.
I got 2 good matched pairs from 6 Caps, so I'll attack C4, then C7.
Unfortunately, modding won't be possible until the weekend, but I'll post my first impressions then. I also have a couple of 20uF Solens to compare them with, but this will take a bit longer....
Cheers,
Ron.
Remember ... you need X hours to run them in properly! aa
Good luck!
Andy
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Hi Ron
how did you obtain the Wima's?
I dont assume you ordered 100+
?
kyrill
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Ron,
Would you also mind explaining how you matched the caps.
Thanks,
West
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Andy,
I'd expect at least a few days burn-in for the wimas from what I've seen elsewhere, around a week to be conservative, although one person has reported 800 hours :o.
The Naim modders on the Pink Fish Media forum are using the 10uF versions as coupling and feedback caps with some success, so I'm optimistic that these will work well. (I'm part of a group buy for some of these at the moment, but we also fell foul of the 12 week lead time).
Kyrill,
The only place I've found that has these in small quantities is http://www.tawelectronics.com/ (http://www.tawelectronics.com/), but they're expensive! :icon_frown: I got 6 at 11 USD each, around double the price you'd pay for a minimum bulk order.
West,
I have a digital multimeter with capacitance tester built in, so matching the caps was just a case of testing each cap and finding the closest values. I usually write the real value in pencil on the side of the cap, in case they get "Shuffled".
You can get a DMM with capacitance tester for a reasonable price nowadays, but make sure the range of measurement is to your requirements.
Cheers,
Ron.
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Ron following yr link and seeing all those Wima caps
http://www.tawelectronics.com/wima_film_capacitors.htm
why was chosen for the
WIMA MKS 2 film
Metallized Polyester (PET)
Film Capacitors in PCM 5 mm, max. is 22uF
and not for
WIMA MKP 4 film
Metallized Polypropylene (PP) Film Capacitor
PCM 7.5 mm to 37.5 mm, max. is 33uF
as in general pp ( teflon like dielectric constant) sound (so) much better than polyester?
-
Hi Kyrill,
The reason for looking at the MKS2XL is: Size! Lead spacing is 5mm, and dimensions are 11 x 16 x 7.2 mm
It should fit on the GK-1 board with minimal disruption.
The MKP4 in 22uF has a lead spacing of 37.5mm, and dimensions are 20 x 39.5 x 41.5 mm, which means mounting off board with flying leads.
The MKS should be an improvement on the original Electrolytics at C4, even if they've been replaced with Black Gates.
I'm also going to test Solens as a comparison to the Wimas, but the Solens are also rather large, and will be "hanging" from the board by their leads.
Cheers,
Ron.
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West,
Thanks for organizing the group buy... you can write me down for 8, 10, or 14 depending on how many people sign up.
I would like to wait until the Wimas have been compared to the Solens though.
I still owe you a bunch of Orion info by PM. Thanks for your patience. I've been very busy, but I'm starting to emerge from the forest and should have time to write in a few days or a week.
Thanks again,
Peter
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West,
Thanks for organizing the group buy... you can write me down for 8, 10, or 14 depending on how many people sign up.
I would like to wait until the Wimas have been compared to the Solens though.
I still owe you a bunch of Orion info by PM. Thanks for your patience. I've been very busy, but I'm starting to emerge from the forest and should have time to write in a few days or a week.
Thanks again,
Peter
Peter, I will mark that down. I have also order a capitance meter so I can match them as best as I can.
I agree about them being compared to the solens first, and don't think I will start a specific thread about the group buy until then.
I'm glad to hear that things are clearing up, and hopefully we can resume our discussions on the orion. Just yesterday I ordered $780 worth of sonicap platinums!!!
-West
(I typed this from my phone, so please excuse the errors)
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Peter, I will mark that down. I have also order a capacitance meter so I can match them as best as I can.
I agree about them being compared to the solens first, and don't think I will start a specific thread about the group buy until then.
I'm glad to hear that things are clearing up, and hopefully we can resume our discussions on the orion. Just yesterday I ordered $780 worth of sonicap platinums!!!
-West
[/size]
Hi bro
we are bro's all of us
audiophile bro's :thumb:
I somehow assume the Solens will sound better than the Wima's but maybe not :green:
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Thanks Guys,
This is Open Source high end at its best, and I really appreciate the work, the passion, and the willingness to share. It also takes faith, and a certain risk - West for example, spending $780, West, go to the top of the class!! Thank you all!!
Kyrill, the laws of engineering are thus:
#1 If it's better, it generally costs more
#2 If it's better, it generally is much bigger
#3 If it's better, it generally is at the expense of some other quality....
:nono: :scratch: :scratch: :duh: :duh:
- and there endeth the lesson. Ain't life grand?? :drool:
Cheers,
Hugh
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You just wake up or you should be in bed a long time ago Hugh:D
I found this on Ebay
(http://i12.ebayimg.com/03/i/000/ag/8a/47b3_1.JPG)
http://cgi.ebay.com/PP-Capacitor-47u-500V-PIO-Oil-Cap-300B-2A3-KT88-EL34-WE_W0QQitemZ290225337115QQihZ019QQcategoryZ71573QQtcZphotoQQcmdZViewItem
PolyPropuleen Capacitor 47u 500V PIO Oil Cap Hugh's universal law #2 applies here
but is it too big? price 12.50
-
This is Open Source high end at its best, and I really appreciate the work, the passion, and the willingness to share. It also takes faith, and a certain risk - West for example, spending $780, West, go to the top of the class!! Thank you all!!
Working with preamps & amps that are as top class as yours, it takes a lot to get them to that next level.
Thanks Guys,
#1 If it's better, it generally costs more
Hugh
You seem to have ignored that when pricing your gear. :wink:
So I guess its a thanks to you Hugh!
-West
p.s. Here is a link to the Solen's. I don't think they will be found cheaper, as this is direct from the manufacture. I have contacted them to ask about price breaks https://www.solen.ca/pub/cms_nf_catalogue_fiche.php?id=1396&recherche=&numRows=10&manufacturiers=26&niveau1=1&niveau2=3&niveau3= (https://www.solen.ca/pub/cms_nf_catalogue_fiche.php?id=1396&recherche=&numRows=10&manufacturiers=26&niveau1=1&niveau2=3&niveau3=)
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i found this about among others, the Platinum
http://www.tempoelectric.com/caps.htm :scratch:
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Kyrill,
Don't believe everything you read here - I have tried the RT from RelCap and I'm absolutely convinced polystyrene is not as good as the teflon. I did not see his test rig, either, so there are still some questions to be raised.
Cheers,
Hugh
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i found this about among others, the Platinum
http://www.tempoelectric.com/caps.htm :scratch:
Kyrill,
Good find, and good read. It's all subject to interpretation, and inherent biases of the testers, of course. I tend to find with these things that when one finds one's favorite thing at the top then it's all GREAT, but when one's favorite is not favorably found, then it's AN INHERENTLY FLAWED TEST.
Steve
-
Might find this interesting as well: http://www.sixmoons.com/audioreviews/caprolling/caps.html (http://www.sixmoons.com/audioreviews/caprolling/caps.html)
I think it affects all of us more as well. He makes a very good which is that certain caps might be highly regarded, but at the end of the day, it what works well in a certain circuit and what sound good to your ears. From what people have said here, in Hugh's products, it’s the platinum.
Now if someone was willing to conduct these tests with the GK-1, have multiple listeners, and then a list like this was produced...I would say it mattered more. Clearly certain caps will just work better in certain places.
-West
EDIT: Also I realized that we can get the Solens from Michael Percy for $30 per matched (1%) pair as long as we buy at least 5 caps. He might also be able to give a litter bit bigger of a discount for a lot more, but its doubtful as his prices are already extremely low, especially considering he will match the caps to 1%.
-
i found this about among others, the Platinum
http://www.tempoelectric.com/caps.htm :scratch:
Kyrill,
Good find, and good read. It's all subject to interpretation, and inherent biases of the testers, of course. I tend to find with these things that when one finds one's favorite thing at the top then it's all GREAT, but when one's favorite is not favorably found, then it's AN INHERENTLY FLAWED TEST.
Steve
Do have C4 and C7 the same value? I have to find my building instructions somewhere to find out
:lol: you start to understand human nature, w e l c o m e my dear friend :thumb:
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Hi all,
Here's an update on the C4 and C7 testing so far:
The GK-1 boards have been returned to "Mildly Tweaked" status, reversing the "Ginger" mod which affects C4, and others which use off-board components.
For the record, The GK-1 is now stock except for:
C1 = Sonicap Platinum 1uF
C6 = Oscon 47uF 20V
C11 + C12 = Nichicon Gold Tune 100uF 63V
C10 + C14 = Nichicon KZ 100uF 50V
C19 = Original 10nF Polystyrene bypassed with 120pF Polystyrene
C21 = Original 1uF Auricap bypassed with 4.7nF RTE
There are Riken Ohms at the following positions: R5, R9, R11, R22, R26a, R26b.
Next up was fitting the Wimas into the C4 and C7 positions. After drilling 2 small holes to accomodate the lead spacing, they fit on the board! See here for details: http://www.audiocircle.com/index.php?action=gallery;area=browse;album=423
Testing Method:
I can usually detect the downgrade of a component much easier than an upgrade, so I thought I'd start with the Wimas (as they're in there already), then the Solens, then Wimas again, with my previous best, Black Gate 'N' (C4) + Oscon (C7) to finish.
The output to the LF55s will be taken from the Sub-Out connectors, so as to only include the SS section in the tests. This should make differentiating between the caps easier.
Next Step:
I need to fit the boards into the case and start burning in!
Cheers,
Ron.
-
nice Ron
I will follow this post as a hungry eagle a fat rabbit(z) :thumb:
PS the C19 is a very import node in the musical network
is this the best "tweak" you can soundwise think of?
-
Hi Kyrill,
I was thinking of putting the V-Cap TFTFs at C19, but if I take the output of the SS circuit though a stepped attenuator and into the LF55s, the whole Valve stage is bypassed, including C19.
First of all let me say I'm no EE. Not even close! :icon_lol: Both Hugh and the tweaking community here have given the GK-1 stellar performance, which I am in awe of! :notworthy: Philip was the one to suggest replacing C4 and C7 with Solens, I just proposed the use of the smaller Wimas.
However, I do have one or two ideas around earthing and power supplies to investigate, but they require lots of time for design and testing, which I try to fit in around my day job, family commitments, etc..... Rest assured, If I do find something that gives an improvement, it'll be published here.
BTW, the capacitor tests you referred to in an earlier post were conducted with all Valve equipment. i.e. High voltages across the capacitors under test. Caps do have different characteristics depending on the DC component of the voltage across them, which could explain why there are so many differing results.
Cheers,
Ron
-
Hi Kyrill,
I was thinking of putting the V-Cap TFTFs at C19, but if I take the output of the SS circuit though a stepped attenuator and into the LF55s, the whole Valve stage is bypassed, including C19.??for a sub woofer OK, but for midrange and highs as well? I will surely miss the tube 3D and "gestalt" unless one uses a tube power amp?
First of all let me say I'm no EE. Not even close! :icon_lol: Both Hugh and the tweaking community here have given the GK-1 stellar performance, which I am in awe of! :notworthy: Philip was the one to suggest replacing C4 and C7 with Solens, I just proposed the use of the smaller Wimas.
However, I do have one or two ideas around earthing and power supplies to investigate, but they require lots of time for design and testing, which I try to fit in around my day job, family c -----------------------
Cheers,
Ron
-
Hi Kyrill,
This setup is just for testing, to make it easier to hear the effect of the Cap changes. Once testing's finished, I'll revert to the Tube stage output. There's no way I could live long term witout the Valves!
Cheers,
Ron
-
Ahh..
you had me worried, but in vain :green:
-
Ron, Kyrill,
I had a long response to Ron's post set up yesterday, but it slipped away during a clumsy keyboard manoeuvre, perhaps because the bloody cat was on my lap at the time..... (I love cats, I often feel the world's problems vanish when you stroke a cat).
Ron, thank you for this seminal work. One of the engineering truths seems to relate to size and quality; if C4 is to be really good, it will be LARGE. I suspect that the Solen will be the go, but if the Wima, with its much smaller size, does the job nicely, then we are quids ahead. Are they 22uF or 47uF?
The quality of C7 is very important, too. This is because the front end of the SS section is highly susceptible to noise injection, and C4 and C7 shunt this noise to ground, preventing it getting into the long tailed pair, T1/T2. Better caps in these positions will a quieter preamp make.....
I don't think C19 can be much improved upon, a polystyrene is just fine here, and in any event no AC current flows because it's driving an ultra-high impedance tube grid (4.3M). C21 might go well if you bypass it with a 47nF teflon, just to pick up on high frequencies.
Aside from that, I can think of no other caps which matter. C18 shunts noise from the tube supply; it could be bypassed with a 470nF teflon, I guess, but it would be very bulky; C20 carries signal, but to the drone cathode follower, which merely serves power supply duties, not in the audio chain; C10/C12 might be replaced with Black Gates but even there I doubt it would have much effect.
Cheers,
Hugh
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Hugh,
That is really useful
Thank you +++
Theo
-
Hi Hugh,
The Wimas are 22uF, the 47uFs are massive in comparison, somewhere around 10x the volume!
I have 20uF 250V Solens for the comparison, so the Cap values will be fairly close. There are also some Sonicap Gen I 20uF 200V in the parts box - there might be time to try these out as well.
Cheers,
Ron
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Hugh,
thanks for all the information.
I hope this isn't getting into the territory of trade secrets but it seems C4 relates to higher frequency while C7 is presumably lower frequency? Is there overlap here or from the point of view of listening tests, is there some sort of midpoint/frequency above which it's mainly C4 and below which we're listening to C7 or is this entirely too simplistic :scratch: .... or just wrong :lol:
jules
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Ron - Have you by chance gotten around to doing a comparison with the Solens & Wimas yet? The Sonicaps Gen I will also be an interesting comparison.
I think a group buy might be the way to go no matter which cap we choose, but I just want to make sure we pick right first. Also if we go with the Solens, since Michael Percy has a great price already, so the 10% won't be a gigantic discount, but I guess at the end of the day its still a discount. Also, Solen themselves was telling me the price would be $15 per cap, which would be unmatched, and compared with michael percy's $14.85 (10 caps or more) for 1% matched caps, it makes no sense to go direct from Solen.
With the Wimas, the discount would probably be more than with the Solens, but I have somewhat of a gut feeling the solens will sound better.
-West
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I dont care what you guys do
as long as you count me in :rotflmao:
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me too
Hugh could you find in your mail with search all previous sold GK-1
and provide the emails ( not with this forum of course) so one of us can warn them for this "opportunity"?
kyrill
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Hi Kyrill,
Sadly, to go through all my records, hundreds of them in a BIG filing cabinet, and pull out emails would:
1. Take about ten hours,
2. Deliver many old, unworkable email addresses, and
3. Violate privacy, at least in the eyes of a few (whom one must consider first!!).
I really don't want to do this; my take on this issue is that AKSAphiles know there is a forum, all they have to do is log on and show their interest!! I set it up through AC precisely so it could be a semi-formal, anonymous (viz lurker) point of contact with the provision to use the PM channel directly to me.
I have been asked to do this before, of course, and to my discredit have never set up an effective database of this information since tax law requires hard copy of all transactions made out at the time of sale. Consequently, I'm reluctant, with my very limited manpower, that I want to duplicate that effort when so many technical and marketing issues dominate my waking hours.
Come to Oz, Kyrill, be my house guest, and have complete access to all my files!! It's not so difficult, lots of dollars, four barbiturates, and two long sleeps, and you're here!! I will pay you with kafe and foccacia!!
I think you'd like Australia......
Cheers,
Hugh
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I think you'd like Australia......
Especially if you visit Sydney as well.
:green:
(J/K Hugh! - friendly inter-city rivalry for those who don't know ;) )
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OK i understand :) Didn want to suggest a thorough approach, but I see yr point ;)
and especially Sydney..;)
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In all seriousness, I am well overdue to visit Melbourne again. Ah... if only it were just a few hours down the road.
-
John,
Likewise, wiseguy........ (the words of the immortal Groucho :notworthy:)
Kyrill, buy that ticket early, next quarter Tapis crude will be $150 a barrel!
Cheers,
Hugh
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Hi Kyrill et al,
Been away with work (including Sydney) so haven't posted for a bit but happy to register an interest in any upgrade and especially fascinated by the Solens possibilities. Currently looking at adding a stepped attenuator so I might talk through all of my options with Hugh following his excellent 07 May summary post. Unfortunately, I am most definitely a follower rather than a leader when it comes to hifi experimentation and to this point I have been thrilled not only with Hugh's design, but the Platinum update to it. So providing I can find room in the case, I'm very interested.
Re Sydney rivalry, just to risk getting us totally off track. As a born and bred and enthusiastic Melburnian, albeit having spent a large chunk of my working life in the Sydney environs, the last few days up there have reminded me just how bad Melbourne drivers are in comparison. It's hard to believe that driving in two cities in a largely common Australian culture could be so different. Still, if one can stay off the roads as much as possible, the restaurants and theatre etc are great here and better still, Aspen is just up the road. :D
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Hi all, my first post here. My GK-1 just recently celebrated it's 1st birthday and received the platinum upgrade to celebrate the occasion. I just went with the 1µf Sonicap at C1 as it seems that most agreed this offered the greatest BFYB.
While I was at it I also swapped the the pot for a DACT stepped attenuator, and converted the input switching to reed relays instead of the Lorlin switch. I've only had one night of listening since the upgrade but I can safely say that I'm rapt with the result, It sounds superb.
Many thanks to those who spent their time so these upgrades are available for us lurkers. :D I'll be watching to see what the outcome of the changes to C4 and C7 is, might try that one next.
Cheers
CJ
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Hi curly joe and welcome.
Did you research/compare the DACT with any other attenuator or just take a punt? Does it have good feel (torque) in the switching action etc.?
:)
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Hi Curly,
Sounds like you’re having a great experience with your Gk-1. I personally went all the way with a TKD pot bypassed by vishays, but from what I hear the DACT is great! RonR is doing us all a huge favor by comparing the caps, and once he is done, I'm going to set up a group buy for whichever one he chooses. I'll make sure to give you a heads up when that comes around. :thumb:
On that subject...RonR...anything on the comparison yet?
-West
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Hi LM,
No, I didn't do a lot of research, other than a quick google search to get some feedback from other users. It all seemed positive so that was good enough for me. I also chose the DACT as it was available locally, through soundlabs group and looked easy to integrate into my pre. If I was going to get fussy I might have gone for a ladder type attenuator rather than the series type but I'm happy with the DACT. It's also a lot more compact than some of the other units which made easy to fit in, not a lot of spare space available.
The feel of the unit seems fine to me, it has a smooth action, the steps are obviously noticeable but definitely not cluncky. It's a bit "lighter" to rotate than the supplied blue alps pot (which felt very nice in operation). I've only been using it for one night but happy with it's performance so far. It also seems well suited to the Gk-1 with my usual listening volume positioned just below the 12 o'clock position and fine enough adjustment to get volume set where I wanted it.
It's the first stepped attenuator I've bought or used so take that into account when reading the above, but I'm certainly happy with it.
http://www.soundlabsgroup.com.au/p/DACT-CT2-2/DACT+Stepped+Attenuator+-+Stereo (http://www.soundlabsgroup.com.au/p/DACT-CT2-2/DACT+Stepped+Attenuator+-+Stereo)
Cheers
CJ
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G'day whubbard,
Yes I had a grin from ear to ear while listening last night, very much enjoying what the pre does for my system. I didn't realise how much I'd missed it until it was reinstalled.
Thanks for the offer of a heads up on any group buy, id definitely be interested, much appreciated. :D
Cheers
CJ
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RonR is doing us all a huge favor by comparing the caps, and once he is done, I'm going to set up a group buy for whichever one he chooses. I'll make sure to give you a heads up when that comes around. :thumb:
On that subject...RonR...anything on the comparison yet?
-West
Me too, please, Westy. (I too have a TKD'd GK-1! :thumb: )
Regards,
Andy
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Spread the word, spread the word :beer:
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I thought it was about time I reported in on the testing so far, so here's the (lack of) Progress report on C4 + C7 mods:
WIMA Caps were installed in the SS section of my GK-1, and left to burn in for 4 days.
Solen caps were then installed, and left to burn in for 4 days.
Unfortunately, during the Solen burn-in I contracted a heavy bout of Man-flu, so any attempt at a comparison between caps in my current blocked-up state would be pointless. :violin:
Hopefully I'll be over this in the next few days, then the testing can begin!
In the meantime, I'm open to suggestions for CD tracks to test with. Ideally, I'd like something with lots of fine detail in the background, and a mix of styles, instruments, acoustics, etc.
My short-list so far:
Steely Dan - Two against Nature
Eagles - Hell freezes over
Delius - Summer night on the river - Beecham / RPO
Nirvana - Nevermind
Nitin Sawney - Beyond skin
All suggestions gratefully received.
Cheers,
Ron
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on the Sheffield XLO test record (CD) are fine tracks unless you dont have it :)
wish you a fast recovery
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Hi Ron,
If you can get into some Cuban, Buena Vista Social Club, st, all live off the floor and superb in the room realism ;). But ultimately best I find to cover all styles like you suggest when testing a tweak or new design , from some good heavy rock, metal to light jazz, bluegrass, haha,the only catch is obviously finding something VERY well recorded of course as many can attest to. I have noticed that the better the resolution gets the more I really enjoy live recordings much more than their multitracked counterparts unless well done, ala say Al Shmidt, and the guys who still remember how to incorporate Real room ambience that doesnt come from a digital list in Pro Tools :).
Colin
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In the meantime, I'm open to suggestions for CD tracks to test with. Ideally, I'd like something with lots of fine detail in the background, and a mix of styles, instruments, acoustics, etc.
My short-list so far:
Steely Dan - Two against Nature
Eagles - Hell freezes over
Delius - Summer night on the river - Beecham / RPO
Nirvana - Nevermind
Nitin Sawney - Beyond skin
All suggestions gratefully received.
Hi Ron,
In terms of superbly recorded stuff (as well as yours above):
Dire Straights "Private Investigations" (the recent "Best of" release on Mercury) - particularly "Sultans of Swing"
Mark Knopler "The Ragpicker's Dream"
Jennifer Warnes "Famous Blue Raincoat" - particularly "Joan of Arc"
Jennifer Warnes "The Well" - "The Panther"
Leonard Cohen "Ten New Songs" - "Alexandra Leaving"
Isao Suzuki Trio "Black Orpheus", on Three Blind Mice
"Wagner for Band", on Mercury (Frederick Fennell & the Eastman Wind Ensemble)
Bob Marley "Chant Down Babylon", on Tuff Gong/Island
Bizet/Shchedrin "The Carmen Ballet", on EMI
Looking forward to your report.
Regards,
Andy
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Jens once you made a special disk with audiophile numbers
can you give some titles?
i am fond of Mercury living presence cd's all classic
for piano and its high overtones besides body and wood tones :
Byron Janis Liszt - Piano Concertos Nºs 1 & 2
especially numbers 10-16 ( piano solo) PM me for tactical details
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Great suggestions guys, keep 'em coming....
Kyrill, the Sheffield disc is now on order along with a Chesky "Ultimate demo disc". Although I have the Hi-Fi News test record on vinyl, the only test CD in my collection contained sine, square + sawtooth waves at differing frequencies and phases, not best for testing fine detail!
Ah yes, Jens' CD, I always meant to ask for a track listing for that.
Just had a look through my CDs, and I've added these to the short list:
Buena Vista social club - thanks Colin
Bob Marley - Legend - thanks Andy - I didn't know there was so much emotion in the man's voice until it was played through AKSA gear!
Jazz at the Pawn shop
I'm looking into the others.
Cheers,
Ron.
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Ah, yes,
Pawn at the Jazz Shop, always enjoyed the detail in that recording, very nicely done......
Thanks Ron, Kyrill, West, Andy, CJ, Colin and others,
Cheers,
Hugh
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Ron,
I too will put my vote in for Dire Straights. Make sure you listen to Walk of Life!
Andy, I laughed pretty hard when you called me Westy, as that is my nickname. For whatever reason, no matter where I go, people slowly gravitate towards Westy. Luckily I don't mind it at all. (Another common nickname has been 'North'...from all those true comedians out there)
While Ron kindly handles all the testing, I have another question to throw out there into this thread. Has anyone experimented with putting in an ELMA or other rotary switch? Has the difference over Hugh's been noticeable? I know Curly Joe used reed relays, but I would rather stick with a good rotary switch.
-West
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Guys,
The CD a few of you are referring to is a compilation I put together a few years back. I called it "My Music"
The tracklist is here:
1. Yello: Get On (from Motion Picture)
2. Eva Cassidy: Over the Rainbow (from Songbird)
3. Mussorgsky: Pictures at an Exhibition, Promenade/Gnomus (from Dorian DOR-99117, gold version)
4. Mickey Hart: Temple Caves (from Planet Drum)
5. Jennifer Warnes: The Panther (from The Well)
6. Johan Strauss: Die Fledermaus, Act III, excerpt (from Deutsche Grammophon 457 766-2, Original-Image Bit-Processing version)
7. Anúna: She Moved through the Fair (from the compilation The Celtic Circle)
8. Titanic: Hard to Starboard (from the original soundtrack)
9. Sinead O’Connor: In My Heart (from Universal Mother)
10. Kodo: O-Daiko (from Heartbeat Drummers of Japan)
11. Shostakovich: Symphony No. 5, 2nd Movement, Allegretto (from Decca 425 066-2)
12. Gladiator: The Wheat/The Battle (from the original soundtrack)
13. Patricia Barber: Romanesque (from Café Blue)
14. Bliss: Song for Olabi (from Afterlife)
Please note that some of the CDs where tracks are taken from are no longer "in print". But you may be able to source most of these CDs second hand.
I'm working on a second "My Music - the Emotions" compilation, but it's slow work, and my private life is getting in the way (divorce, selling house, moving etc.).
It will get there, eventually :wink:
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My long time ,favorite disc, at least for female vocals has been Diana Kralls, Love Scenes. Live in Paris is another DK disc I pull out when evaluating gear, fantastic live recording .... Oh, and add another vote for Private Investigations on the best of CD. :D
Ron,
I too will put my vote in for Dire Straights. Make sure you listen to Walk of Life!
Andy, I laughed pretty hard when you called me Westy, as that is my nickname. For whatever reason, no matter where I go, people slowly gravitate towards Westy. Luckily I don't mind it at all. (Another common nickname has been 'North'...from all those true comedians out there)
While Ron kindly handles all the testing, I have another question to throw out there into this thread. Has anyone experimented with putting in an ELMA or other rotary switch? Has the difference over Hugh's been noticeable? I know Curly Joe used reed relays, but I would rather stick with a good rotary switch.
-West
Hi whubbard, my choice of reed relays was based more on keeping my signal paths as short as possible. I originally modified the input switching board so that the HT bypass switch acted on only one dedicated HT input (bit safer with kids and wife using the gear) and relocated the switch to the front panel (for convenience). However, this created a lot of extra wiring for my signal to travel through and I was never really happy with that. Using reed relays has allowed me to cut a chunk of extra cabling out and I feel It's a more professional finish now. Oh, and I have more flexibility with where I can mount switches as well. I went with Coto relays, figured if they where good enough for use in the Bent passives ( I think they use 120 of 'em from memory) they'd be good enough for me. :D
Cheers
CJ
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In the meantime, I'm open to suggestions for CD tracks to test with. Ideally, I'd like something with lots of fine detail in the background, and a mix of styles, instruments, acoustics, etc.
From the first NYAR 2006 Cd.....
1 - Copland - Fanfare For The Common Man
2 - Wynton Marsalis Quartet - Feeling Of Jazz
3 - The Bad Plus - Keep The Bugs Off Your Glass, And The Bears Off Your Ass
4 - Bozzio, Levin, Stevens - Duende
5 - Ben Harper - Gold To Me
6 - Morphine - Buena
7 - Bernadette Peters - Blackbird
8 - Kalman Olah Trio - Inspiration Of Variation XXI
9 - Mino Cinelu - Oncoming Horizons
10 - Nils Lofgren - Keith Don’t Go
11 - Groove Troopers - Bearing Bears and Boring Boars
12 - Stevie Ray Vaughan - Tin Pan Alley (w/ Johnny Copeland)
A nice variety.... :thumb:
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Oh, and I have more flexibility with where I can mount switches as well. I went with Coto relays, figured if they where good enough for use in the Bent passives ( I think they use 120 of 'em from memory) they'd be good enough for me. :D
Cheers
CJ
Curly,
I understand the basics about reed relays, but not much more than that. What did you use for selecting the relays? Would you mind explaining exactly how you set the reed relays up.
I still think I will use either Hughs switch, or an ELMA, as for some reason I think it will be of better quality than a reed relay. The reeds will shorten the path, but the rotary will sound better. If I'm wrong in thinking this, please correct me.
-West
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Hi All,
Many thanks for the track lists, I feel a trip to a CD fair coming on.....
West,
If you want to have an Elma switch AND keep the paths short, you could use a shaft extension like CMScott's one here: http://www.audiocircle.com/index.php?action=gallery;area=browse;album=326&pos=5 (http://www.audiocircle.com/index.php?action=gallery;area=browse;album=326&pos=5)
Cheers,
Ron
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Hi Ron,
Can't wait to 'hear' the results from your listening tests. Hopefully you can get a bunch of the songs listed.
I am probably going to use some sort of extension shaft, but it will be wood. I am decent at working with metal, but very good at working with wood. What most people do with metal, I plan to do with wood. A dowel will work just fine for an extension shaft, and not only will it be easier to attach, it will also be much cheaper. The only metal that will appear in my GK-1 and Lifeforce amps will be to shield the transformers. The other nice thing about working with wood is that I don’t have anything confining my layout. I can make it as spread out as a wish, and it will just mean a bigger box, which is fine by me.
-West
-
The only metal that will appear in my GK-1 and Lifeforce amps will be to shield the transformers.
-West
Hi West,
But how are you going to shield the GK-1 internals from RFI? :? It's all very well to stop transformer and mains emanations from getting to the PCBs but there is also external RFI which a metal case (earthed to the IEC earth tag) shields against.
If you're going to use wood (and please use wood, not MDF! :D ) then I suggest you need to do what I think Kyrill did ... which is glue (thin) copper foil on the insides of the wooden case and make sure this is earthed.
Hugh specifies that shielded ICs should be used with a GK-1 but this assumes that the PCB itself is shielded from RFI.
Regards,
Andy
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Oh, and I have more flexibility with where I can mount switches as well. I went with Coto relays, figured if they where good enough for use in the Bent passives ( I think they use 120 of 'em from memory) they'd be good enough for me. :D
Cheers
CJ
Curly,
I understand the basics about reed relays, but not much more than that. What did you use for selecting the relays? Would you mind explaining exactly how you set the reed relays up.
I still think I will use either Hughs switch, or an ELMA, as for some reason I think it will be of better quality than a reed relay. The reeds will shorten the path, but the rotary will sound better. If I'm wrong in thinking this, please correct me.
-West
Hi whubbard,
My last post, about my reasons for using reed relays was just my long winded and unclear way of saying that it wasn't for any supposed sonic benefit. :)
Any improvements in the sound of my GK-1 are certainly due to the Sonicap platinums (maybe some from the DACT) rather than using relays, I wouldn't expect that changing a rotary switch for relays, or vice versa would be audible.
As for the implementation, I'm fortunate in that I have screen printing facilities available at my workplace so I was able to redesign a circuit to incorporate them. I use a bank of three relays for each input (L,R and Gnd) and switch them with a rotary switch. I have a PCB mounted encapsulated transformer used as a power supply for the relays and LEDs so as to keep it separate from the audio circuits. I also had (ambitious?) plans to someday use a micro-processor to run all the switching etc. So having the relays in place will help facilitate that if I ever get around to it.
Cheers
CJ
-
In the meantime, I'm open to suggestions for CD tracks to test with. Ideally, I'd like something with lots of fine detail in the background, and a mix of styles, instruments, acoustics, etc.
My short-list so far:
Steely Dan - Two against Nature
Eagles - Hell freezes over
Delius - Summer night on the river - Beecham / RPO
Nirvana - Nevermind
Nitin Sawney - Beyond skin
All suggestions gratefully received.
Cheers,
Ron
Ron,
FWIW, I don't think specific discs matter very much, but discs that you know VERY WELL do matter. That's really the only way you can tell if there is a difference. And because it takes a bit of time to swap out caps, musical memory can play tricks.
This cap change is suppose to lower the electronic "noise" and is not in the signal path, thus the benefit should be a lowered sound floor and an increase in low level information, if it's there at all. Classical discs have this in spades, but if that's not what you listen to, well, then.......
Steve
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Andy,
Thanks for the advice. I think I'll get a 5 foot roll of .01 copper just to put in the whole case, and also a few pieces of TI shield for the transformers.
Curly,
That makes sense, but for me, would not be very practical, especially because I don't want another transformer in my case. However, hopefully it has worked well for you. Did you find it introduced any extra noise?
-West
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use as well next to the copper foil, kitchen aluminum foil, 1+1=3 :)
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Kyrill,
That should be easy to do. It will also have the added benefit that aliens will not be able to take over my amplifiers! :thumb:
If I have a layer (or two) of a combination of copper and aluminum foil between the transformers and the amp boards, do you think that will be enough, or should I use the TI shield for that, and just use the copper/aluminum for the overall sheilding of the box.
Also does anyone have experience with both the Elma and the Dact? is the Dact switch worth the added cost? With the elma, have people noticed a difference between switching both hot and nuetral, or just hot?
Thanks for all the advice guys.
-West
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west, andy,
Is it an assumption that copper is the best shield? I always thought (assumed ) aluminium or nickel were good.
The frequency(wavelength) one is trying to block out must also determine the material used
-
Hi West,
I'm pretty sure the DACT uses an ELMA switch, made in Switzerland. They are high quality switches, very durable, with a nice feel to the action. I suspect that DACT offer slightly better resistors in their design, but can't be sure.... I'll be guided by others here who might have bought them in the past.
Hope this is helpful, there ain't nuttin' new under the sun!!
Cheers,
Hugh
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Hi West,
No, there was no extra hum, the extra transformer is pretty small and encapsulated as well. My pre has a slight 50hz hum, but it was there before my mods, it's something I want to work on next time it's apart.
Cheers
CJ
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west, andy,
Is it an assumption that copper is the best shield? I always thought (assumed ) aluminium or nickel were good.
The frequency(wavelength) one is trying to block out must also determine the material used
Yes, that is correct. That is also what makes the TI Shield special. Texas Instruments made the proprietary clad metal so that it would block a bigger spectrum.
I am using the Copper on the basis that many others use for shields. I did look around for more information on what blocks what...but came up fairly empty. It is rare that I will just jump onto a bandwagon like this (I like doing research), but I think the copper will do just fine. Especially when combined with the aluminum, which should block some other frequencies. I don't think I'm going to use the TI shield as it was a bit too expensive. What I am going to do is look into what I should use to shield the transformers in my GK-1. I think that a steel plate, then a copper layer, with some aluminum foil over would sure shield them, but I'm not sure.
Also, I just went ahead and got the DACT selector switch from Kevin at diycable.com. Hopefully it was worth it. At this point it's looking like my GK-1 is going to be as good as it gets (if it weren't for the Swift...)
Curly,
I'm praying to avoid hum, but I have a feeling its something I'm going to have to deal with.
-West
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I'm pretty sure the DACT uses an ELMA switch, made in Switzerland.
Yes, it looks like that to me too Hugh. As far as resistors go, you get to choose. From Michael Percy you can get Holco or Roderstein [if they haven't run out] but you could just buy use whatever you want if you are DIYing and you could even choose different resistors for the signal and ground sets. I've used an Elma attenuator and an Elma source select switch here:
http://www.audiocircle.com/index.php?topic=54068.10
but I can't make any comparisons with Hugh's stock rotary as my GK-1 was built the way it is.
Thin copper is fine for RF shielding but thickness counts when it comes to magnetic shielding. Somewhere, sometime, Occam suggested that 10mm of copper only had a ~30% shielding effect on magnetic fields [approximate memory too :)]. Mild steel or stainless steel that has slight magnetic properties, seem to do the job on magnetic fields. Keep in mind that magnetic fields fall away fairly rapidly so distance is your biggest ally. RF on the other hand doesn't :), so the shielding needs are slightly different.
jules
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Thin copper is fine for RF shielding but thickness counts when it comes to magnetic shielding. Somewhere, sometime, Occam suggested that 10mm of copper only had a ~30% shielding effect on magnetic fields [approximate memory too :)]. Mild steel or stainless steel that has slight magnetic properties, seem to do the job on magnetic fields. Keep in mind that magnetic fields fall away fairly rapidly so distance is your biggest ally. RF on the other hand doesn't :), so the shielding needs are slightly different.
Jules,
This was basically what I had guessed the properties were, and luckily you were able to pretty much confirm it. I think I will stick with my current design. Copper for the whole box, steel between the path of the transformers and the amp modules.
-West
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from a purists side i would not invite magnetic metals to enter my house of sound
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Hi West,
I'm pretty sure the DACT uses an ELMA switch, made in Switzerland. They are high quality switches, very durable, with a nice feel to the action. I suspect that DACT offer slightly better resistors in their design, but can't be sure.... I'll be guided by others here who might have bought them in the past.
Hope this is helpful, there ain't nuttin' new under the sun!!
Cheers,
Hugh
DACT uses Elma switches and smd resistors. They are almost exactly the same as Goldpoint, which now uses Elma switches and smd resistors.
Neither DACT nor Goldpoint use the BV switches though. DACT does give cleaning instructions in case there is switch noise, as there can be with the kind of switches that they use. DACT is made in Thailand. GP is made in Colorado now, or at least the company is based there now.
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from a purists side i would not invite magnetic metals to enter my house of sound
Purists position has respect here but perhaps I can add the point that one of the stainless steels most commonly used for folding/case making, 304, is mildly magnetic. It won't hold a magnetic field and it's actually hard to detect that it has any magnetic properties but it resists the sort of AC generated magnetic fields you get in audio which is quite useful.
jules
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Thanks Jules, might have to give some 304 a shot and see how it sounds. I'll try and make it easy to remove so I can compare with other metals. Any other favorites for blocking AC magnetic fields?
-West
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Ron.
Waiting here with baited breath. Any preliminary findings on the Wima, Solens etc cap shootout? I need something to get my mind off stepped attenuators. :D
-
Lyn,
I enjoyed that.......
This virus does have good and bad days..... :icon_twisted:
Hugh
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Ron.
Waiting here with baited breath. Any preliminary findings on the Wima, Solens etc cap shootout? I need something to get my mind off stepped attenuators. :D
I sent a PM to Ron about this earlier today but haven't heard back yet. I didn't want to push him into making a premature decision, but I do want to start putting together some information for the group buy. I've put together a little bit of on both (prices & times & matching), but I want to really figure it all out for one of the caps soon. I'm just looking for solen>wima or vise versa, not solen is 2.43 times better than the wima, if you know what I mean.
-West
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West,
if you're still in the planning stage, you can allow whatever space you need so you should be able to fit a Solen/Relcap/other sim. without trouble. If you're ordering one of those hugely expensive TDKs from Michael P. you could simply add a set of caps to that order. You won't be saving anything after postage is added by going for a group buy and it really doesn't look as though there's going to be the numbers to get a significant cut. These caps aren't all that expensive to start with!
It could be hard to get an early response from other testers on this one as these caps do take time to break in [I thought only BGs did this till I found something similar with the Platinum C1s].
On your earlier question ... maybe the answer should be platinum for this thread but ordinary steel is the tried and true material and it's got a lot going for it. Of course, if you put things in separate boxes as kyrill has, you do away with the magnetic interference problem so you can use wood [with RFI shielding] and wood is good :). Check the gallery, there's some great designs. the main thing seems to be to put the transformers in their own compartment.
jules
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Re Bypass/shunt resistors on stepped attenuators,
where does the resistor actually go from-> to on the GK-1 basic non switching version , if I already have a cheapie attenuator .
Is it worth adding this mod to the mix.
Theo
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Jules,
I would have just gotten them from Michael, but I too am going to wait and see if its worth getting the Solens. Also, it is possible that with the group buy we will save around 20% which is worth it to me. The other advantage of the group buy is that I will be able to give people matched groups of 4. For my Gk-1 there is a chance I will still go for two boxes (as my amps will be), but I'm just not sure at this point. I'm just going to do my best to make the GK-1 and the Lifeforces as top notch as possible!
Ron has informed me that he will try and have something for us soon.
-West
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Sale is over..
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Ratz............ :scratch:
Hugh
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AAARGGHH! :duh:
I spent half of my lunch hour today typing in the preliminary report on Wima Vs Solen, then lost it all when the browser crashed!
So here's a quick and dirty version:
WIMAs are good.
Solens are better by approximately 30% IMHO. (Better separation of instruments, lower bass, more natural sounding)
I still need to try out the Sonicap 20uF against the Solens, probably in the next week or so.
Cheers,
Ron.
Note to self: NEVER use a Beta version of ANYTHING to do something you don't want to lose!
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Hi Ron,
Many thanks...... nothing like bleeding edge, blood on the modem, I've seen this a few times.... :scratch:
I'm still bowled over by the diffierence this superficially trivial cap gives, I really am. Clearly the issue is noise, in which case a lower noise transistor for the current source might be better. 2N4402, a low noise general purpose PNP rated to 40V, comes to mind.
If only there were small Solens. I have a 39uF SCR sold by Angela in the US which is rated to 630V. It is fully 65mm long (2 1/2") and 44mm diameter (1 3/4") - a freakin' monster, not suitable for this task.
I would imagine this cap is dangling below the GK1 pcb, like a lifeboat on a liner, it must look rather odd. I just wonder if there are ANY metallised polyprop caps rated to say 50V, they would be far smaller and more manageable. I know Philips made solid block polyesters to 100V, but they would be too large as well. It seems there is NO free lunch!
Thanks for posting Ron, how are the VSonics coming along?
Cheers,
Hugh
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AAARGGHH! :duh:
I spent half of my lunch hour today typing in the preliminary report on Wima Vs Solen, then lost it all when the browser crashed!
So here's a quick and dirty version:
WIMAs are good.
Solens are better by approximately 30% IMHO. (Better separation of instruments, lower bass, more natural sounding)
I still need to try out the Sonicap 20uF against the Solens, probably in the next week or so.
Cheers,
Ron.
Note to self: NEVER use a Beta version of ANYTHING to do something you don't want to lose!
Hi Ron, thanks for your time in evaluating these caps. Comparing the Platinum Sonicap upgrade (for C1 & C19) that was done recently to this upgrade (using the Solens), how would you rate the improvement in sound between the two. The Platinums providing more of a difference or not?
cheers
Tim
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TKD and Solens upgrade.
As I mentioned on the attenuator thread, I received a 10KOhm TKD from Michael Percy this week together with some Solens Caps as I thought I might as well get one package and only have the GK1 down for just a single upgrade. Had it all back together last night but with only time for a quick check. Trouble is I don’t know which component contributed exactly what change to the sound so I can only comment on the package as a whole.
My GK1 is a basic model only. Stock standard except for Platinum input caps prior to this upgrade. I run a separate external phono stage and have installed a second set of RCA inputs and a switch to allow vinyl/CD source selection.
Yes I know that after fit-out that I should have set the system up on repeat and left any listening (let alone critical) for a 100 hours or so but there was simply no way that I could not sneak a listen today. In any case, I just had to check out the integrity of the new wiring didn’t I? Well I did have a quick listen straight away and while the detail and clarity were obviously an immediate and large improvement, the soundstage was wide but flat and 2D, the sound very thin, a little strident in the treble and virtually no base at all. No wonder people say not to listen till things settle a bit.
So this morning, after about 4 hours of leaving the system playing whilst I mainly did other things, Hugh popped by to have a bit of a listen. We sat down with a variety of LPs and CDs for about 3 hours or so. The improvement of the base alone over this period was amazing to hear. From virtually nonexistent on my first listen, to disappointing at when Hugh first arrived to quite reasonable if not fully acceptable by the 7 or 8 hours elapsed when he left.
My initial impression of the upgrade (apart from the general lack of Wellie from the base) was of an improvement in the order of magnitude of that of the original Platinum installation. The improvement itself was really that of greatly increased refinement and low-level detail. Cymbals shimmer, voices hang in mid air and attack and decay in particular are superb although it was some hours before this really became evident. Base itself is greatly improved in tightness; it’s really only the relative volume in the bottom octave that is still lacking at the moment. The hugely appreciated valve warmth of the GK1 remains but in all other respects it seems to totally disappear.
The TKD is certainly a beautiful control. I’m sure much of the improvement is from it but I can’t see how its resistors would provide as much change during the burn in as the capacitors are probably contributing. Can’t wait to get up 100 hours or so and report back on how it sounds. I’m pretty sure the base will get back to what it was before but I did this upgrade on a bit of a punt so can’t be certain it's the perfect answer. Notwithstanding, it is already a significant upgrade and I am very, very pleased with it.
:thumb:
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TKD and Solens upgrade.
"but I can’t see how its resistors would provide as much change during the burn in as the capacitors are probably contributing".
:thumb:
Laurie, did you install the TKD with its bypassing Vishays or not?
Either way, it seems to me that your comment is a strange one. :o Before you installed the TKD, you wouldn't have believed a mere volume control could make so much difference? (Because it took you so long to be convinced to shell out the money for one! :D )
All you need to do is "stand on the shoulders of the giants who have preceeded you" ... Bob Crump did some exhaustive evaluations (as DSK has posted) and:
1. said that the Vishays improve the TKD, and
2. you need 40 days of 24hr burn-in before it reaches the final sound.
Regards,
Andy
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Andy,
Lyn's TKDs are rated at 10K, and as such we did not fit the Vishays as this would have reduced the impedance a little too much.
In my view, the addition of these resistors is appropriate only if you have a 50K or 100K TKD.
Incidentally, I fitted the C4/C7/TKD to Lyn's GK1 yesterday. The complete job took about four and a half hours. I found it fiddly, fine work.
Cheers,
Hugh
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Andy, as Hugh has said, no Vishay’s. I'm not sure why you think my comment strange; I was simply describing my experiences for those interested. So to clarify. I certainly needed no convincing about the benefits of a Stepped Attenuator, I’ve had a wealth of such advice on this forum including Bob Crumps mods. However, my budget only stretched to getting the best pre made attenuator I could hence the 10KOhm TKD at MP’s current price as discussed at length in the SA thread. I’m perfectly content to say that with the current budget expended, the stock TKD will just have to do for the foreseeable future. 8) My earlier comment that you quote was to the effect that the changes during burn in were so great I’m sure they must be mainly due to the capacitors and masking any burn in so far with the TKD. Sorry if my wording seemed confusing. :?
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As a quickrep, the TKD attenuator and the 24uF Solens have just passed the 30-hour mark and I’m more pleased than ever. :D I think I said at 20 hrs that I believed that the system was approaching a really mature overall sound now with simply amazing detail. I was right about the detail but perhaps a little early on the maturity claim. It’s really quite fascinating how the sound is still changing subtly over time during the burning in process and I can see why hundreds rather than tens of hours are recommended. For a short period the base was almost too much and the treble became a little laid back but as of last thing last night, the frequency balance was excellent, the soundstage had really opened out and imaging is quite 3D including some now in front of the speakers.
Of particular note, the base is much better than before and it was always good following the Soraya upgrade. Really clean, tight and tuneful. I remember reading somewhere a while back that getting the base right in a system is actually more important than most people think. That incorrect harmonics generated from impure or phase shifted base notes can confuse and muddy the higher frequencies. I have no clue if this is really true but it seems to make sense and the lovely base is really underpinning and driving the music and letting the equally clean and detailed mids and treble shine.
I believe that Hugh must have the basic GK1 circuit spot on for such simple component change mods to bring out such great improvements. A lesser circuit could not have benefited so much I’m sure.
Theo came around and had a listen last night and I’m pretty sure he was reasonably impressed with the sonic changes. He already has a stepped attenuator in his GK1 but as to whether he will do the Solens (or some other cap from RonR's experiments) upgrade, only he can say. Thanks again Philip for drawing this cap change to our attention. :thumb:
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Another fine night at Lyn's.
Spent a little over 2 and a half hours listening, and towards the end just kept putting off departure time- always a good sign!
The last 30 to 40 minutes I wondered if I was imagining or actually hearing changes as they were developing.
My initial impression - striking base , too big almost but very clean , fast and very musical. Top end was not a step forward(however I do like my sound a little bright), but that changed dramatically towards the end of the night and that special balance Lyns system always impressed me with was back and better than I recall from previous sessions.
Im still somewhat confused if burn in changes can take place and be noticeable in such a short space of time, but the system when I left was not the same system as when I arrived.
I tried to find other explanations but there were no new adjustments to the system. It got later in the night(and I always find that most systems sound better the further into the night one gets?Power grid noise). Quality variations of recordings were more evident also.
Overall the solens and the attenuator combination is a significant step forward which becomes more apparent with extended listening. There was more of everything in just about the right doses, but in particular the base is superb, on tap when the music calls for it and not dominating. The top end clarity, punch and realism as they should be. The music reaches out to you more and you feel part of it.
As to what Im doing- what ever the group buy decides. Im going to end up with 2 systems the way its panning out.. The "Hughie" for relaxation , savoring and really enjoying the finer aspects of music and the "Head Banger" a grand scale system for its wow factor because I like that too but cant listen to it very long. :thumb:
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Sounds like we pretty much agree about what we heard so thanks Theo, always welcome. Incidently, warming up was not a reason for any change as I had been playing the system for nearly 2 hours prior to your arrival. :D
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Incidently, warming up was not a reason for any change as I had been playing the system for nearly 2 hours prior to your arrival.
Hmmm, Theo, could it be that you grew used to it, and positively enjoyed it after a few drinks???
This effect is very pronounced, happens to everyone, and very difficult to design out. Some say the only way to do it is the double blind test, but to me, it's too difficult to set up and it does not account for individual tastes, which is a big factor in audio as it's such a personal thing.
Hugh
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Hugh,
getting used to it? Possibly had some bearing but was far too pronounced to be the total explanation. Im certain when you go back and have another listen you might agree and i would be interested in your findings.
Lyn could report what happens over the next week. It is an evolution of a new life form he has there in his listening room.
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Lyn could report what happens over the next week. It is an evolution of a new life form he has there in his listening room.
Jeez, what were you guys smokin, as you were listenin! :lol:
Regards,
Andy
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Andy dont get me started on your system.
Is it still sounding like you dont have any speakers in the room?
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Not smoking Andy, drinking!
Hugh, I am quite affronted with people questioning our scientific techniques. It was planned to have been a genuine double blind session - after the second Chivas. But Theo piked after one as he had to drive home so it was only single blind. :P
As to the new life form Theo - still thinking that one through :?
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Andy dont get me started on your system.
Is it still sounding like you don't have any speakers in the room?
Absolutely, Theo! :thumb:
For the last 2 weeks, I haven't had any (working) speakers in the room as I have started the process of installing the Maggie drivers into the new hardwood frames - and this involves cannibalising both to make one! :o
Still a bit to do on the RHS speaker and then I have to do the left ... so it will be at least 3 more weekends! :cry:
Regards,
Andy
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Hugh,
getting used to it? Possibly had some bearing but was far too pronounced to be the total explanation. Im certain when you go back and have another listen you might agree and i would be interested in your findings.
Theo, your wish was my command. :D Hugh popped by for an hour or so today to hear the 34hr old version rather than the 4 to 7hr old version he heard last week. It will be interesting to hear his view but to me it hasn't changed in any way I can pick in the 3 or 4 hours of play since you left.
I don't know about a new life form but the old one has sure picked up its skirts. I'm finding the frequencies perfectly balanced now, wads of fine detail and really solid and realistic depth. I know it still has some settling down to go but I'm already inclined to think in terms of overall system refinement that this has been the most profound change yet. Overall the system now seems highly detailed and very, very musical with seemingly no distortion, quite fatigue free and with great focus and a fabulous sense of 3D space. It's a lovely feeling that words describing why can't really capture but I just keep wanting to put on another LP or CD and keep listening. aa
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Thanks Lyn,
Let me give my impressions. I cycled gracefully around to Lyn's today and heard his system to my complete satisfaction. (And gave Guy, his son, a solo ride on my Kamakazi, hell, he used more revs than I do, quite scary!!). :lol:
A famous track oft used by audiophiles is 'Flight of the Cosmic Hippo' by Bela Fleck. This track is meant to demonstrate huge, grand canyon bass and sharp definition, with a few afficionados saying it also shows great imaging.
I have always found this track spectacular, but focussed more on effect than the music, which is actually pretty good, a nice tune, and beautiful playing.
Today I realised after a few bars (that's music, not chocolate......) that this was the most musical rendition I'd heard, with absolutely nothing to distract from the skills of the musicians. No longer was it a 'hifi' sound; it was completely transparent, with all emphasis on the performance, and extraordinary details revealed at the bottom, near the noise floor, and imaging to die for. :drool:
I guess you'd have to say mission 95% accomplished. I have only to spend the remainder of my life teasing out the last 5%, doubt I'll get there. Not that I can pick anything bad - it really was that good..... :bounce: :drums:
Philip, Ron, my sincere, genuine thanks to you both for making me realise that there was more to come from this six year old design. :thankyou: :rock: :wine:
And thank you Lyn, for being such a determined, patient audiophile! :thankyou:
Cheers,
Hugh
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Lyn, Hugh,
Im glad I heard what I heard and not what I wanted :scratch:
Its a means of playing musical instruments in harmony now , not a hi fi system as you noticed Hugh :drool:
Its such a good feeling when one experiences a system that has crossed into that magical realm.
So you start with a GK1 moded, add some Soraya a sprinkling of mods, the V sonics and you are almost done.
Just be done with it Hugh and complete the chain :thumb:
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Hi,
There is still a question in my mind. Which is better, the original design at C4 with a 24 uF cap or the "ginger mod" with a 67 uF cap at C4. Some brave soul will have to do the comparison which will be time consuming and may be subtle. But the single smaller cap at C4 is the easiest to do. I have the double and larger cap. The present sound from my system is so good, I'm not changing anything soon.
Cheers,
Philip
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I'm not changing anything soon.
Philip,
I'm completely with you. :thumb:
I can't answer your 'which is the best configuration' question (unless it's a purely rhetorical question in which case you already have :) ) but I can thank you again for your discovery. Incidentely, I chose 24uF rather than any other value as It was the biggest I could fit comfortably in my enclosure without excess pain. In other words, I could go bigger than 20 with 24 ideal but 33 and certainly 47 would have been quite problematic to fit in my case. However, the results are so good that even if other brands or sizes prove better in trials, I sure the improvement could only be marginal and I'm quite content with the 95% performance I now have.
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Hi all,
Thanks for being so patient, this "quick test" turned into a bit of a marathon. Here are the results of my testing over the last few weeks.
Firstly, a description of the test equipment and set-up:
1. The split GK-1 boards were removed from their case as there wasn't enough room in the original case for experiments.
2. 2 x 6VA 15-0-15 potted transformers were used, which gave a slightly lower quality power supply than the usual GK-1 transformers.
3. Only the Solid-State section of the GK-1 was used for the test, output was taken to LF55s via a stepped attenuator with Vishays, later upgraded to TKD Stepped attenuator (tests were re-run after installation).
4. A daughter board was added above the GK-1 boards to hold the Caps on test and 2 multi-way switches to easily select which caps were in circuit.
5. C7 options:
a. Oscon SP 47uF + 0.22uF Evox SMR Bypass - The best I've heard until these tests
b. Wima MKS2-XL 22uF
c. Sonicap GenI 20uF + Sonicap GenII + 0.47uF Bypass
d. Solen 20uF 250V
e. Relcap AudioCap 40uF PPMF
6. C4 Options:
a. Black Gate N 47uF - The best I've heard until these tests
b. Wima MKS2-XL 22uF
c. Solen 20uF 250V
d. Sonicap GenI 20uF
e. Relcap AudioCap 40uF PPMF
7. T4 Options:
a. BC557 - Original
b. BC560 - Low noise replacement
8. T1+T2 Options:
a. BC557 - Original
b. BC560 - Low noise replacements
9. The last 3 caps were chosen for their physical size, as most people won't have loads of room in their GK-1 cases for anything much bigger than these.
The results:
I've based the Cap results on a standard score of 50%, which is the benchmark using the Oscons/Black Gates.
1. Wima MKS2-XL 22uF
Moving from the Oscon / Black Gates to the Wimas gave a useful improvement in detail and high frequencies, but these caps only gave around half the improvement to the soundstage of the physically bigger caps. 60%
2. Solen Fastcap 20uF 250V
Natural sounding mid-range, nice treble, accurate bass with punch. The soundstage really opened out with these. 75%
3. Sonicap GenI 20uF
With or witout bypass, the Sonicap was not a success at C7. It lost out on the start/stop of bass notes to the Solens, but still bests the Wimas. 70%
At C4 however, the Sonicap was marginally better than the Solens. There was slightly more high-frequency detail apparent. 78%
4. AudioCap PPMF 40uF
These caps extended the bass by easily half an octave or more. Maybe it was the value of 40uF, or maybe the construction. Sounded "right" and balanced from the word go. Alot like the solens, only a little bit more of everything: Sweeter treble, slightly more open mid-range, extended bass. Soundstage was as good if not slightly better than the Solens. 85%
One caveat with these: The Aksonic speakers I'm using in my system do not have the bass response of the V-Sonics which will replace them. There is the possibility of too much of a good thing here giving a hump in the bass response, in which case I'd go for the 40uF AudioCap at C7 and the 20uF Solen at C4.
5. Changing T4 from BC557 to BC560
There was a distinct lowering of noise by around 25% at full volume with shorted inputs when this transistor was swapped out. I couldn't detect any drawbacks in the sound. Worth doing.
6. Changing T1 and T2 from BC557 to BC560 (Matched)
I couldn't detect any improvement in noise performance with this change, but there was a slight "Mechanical" tinge to the sound with these in place. I was not able to source the same make of transistor that Hugh uses for these. Perhaps this is the reason for the slight degradation in the sound. For the record I used Fairchild transistors, maybe the On-semi version would be better?
Cheers,
Ron.
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Prima Ron
:bowdown: :bowdown: :wave: :hyper: :banana piano:
Great report
Kyrill
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Ron,
Simply incredible, thank you, I will contact you privately later in the day. :thankyou:
Cheers,
Hugh
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The Bob Crump mod,
now that West is about to dispatch the caps for the GK and the hood is coming off the GK I was going to try the Bob Crump mod if I could find a clear description what to do.
Does anyone have a link or a description what to do for a stepped attenuator with resistor steps?
Theo
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Theo, the late Bob Crump asked me specifically not to publish these details anywhere on the web. Out of respect for Bob and the remaining CTC members (Thomson and Curl) I will PM you the details rather than post them here.
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Thank you,
and I will respect those wishes.
reading about one gets the impression he was very much respected. I will look him up and learn a little more about the man and his life.
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DSK, Theo,
Bob Crump was much loved, from what I gather. John Curl presently posts on DIYaudio.com, and has a whole thread devoted to the Blowtorch, details of which he has sparingly released over the last three years.
John is a very testy character, and enjoys a good fight. He's even had a shot at me, for whatever reason I cannot imagine!
Cheers,
Hugh
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This thread has been quiet for a long time, and I've just made some minor changes in my GK-1, so here goes.
T4 - BC560 in BC557 out
C19 grid coupler - .01uf Sonic Platinum out, replaced with 1000pf LCR FSCEX polystryrene
C21 output - wire link out, replaced with stock Auricap bypassed with .01uf Sonic Platinum.
The T4 is from the other thread. I had wanted to return the Auricap as output and use a new Auri-T teflon as bypass, but pcX didn't have them in stock, so I used the Platinum.
I've come to really like the LCR caps from using them in my cd player modifications. With a teflon cap at the C-1 input, the grid coupler doesn't really require a teflon, and the LCR caps are nice replacement if you want to change the stocker. The LCR's are only available from Farnell, AFAIK.
The overall sound change with the about is quite small really. Perhaps a slight noise lowering with the low noise 560. There is quite a bit of voltage at the output, so a cap is best here rather than wirelink, and a teflon bypass of the stock Auricap is a very good way to go.
I think I can weld the lid on now, or at least until I decide to make a bigger and nicer chassis.
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C21 output - wire link out, replaced with stock Auricap bypassed with .01uf Sonic Platinum
Well now here is a funny thing. I just put the Auricap in at C21 as the wire link just wasn't working. Hugh and I could not figure it out for out lives, but with a wire link in at C21 the GK-1 tube section would not work. I am going to be putting in a 1uF Platinum at C21 in the near future, but I have to make sure I have room for it first.
I too will soon be putting in BC560s, however the AudioCaps will have to wait as I know I don't have room for both of them and the Platinums.
-West
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C21 output - wire link out, replaced with stock Auricap bypassed with .01uf Sonic Platinum
Well now here is a funny thing. I just put the Auricap in at C21 as the wire link just wasn't working. Hugh and I could not figure it out for out lives, but with a wire link in at C21 the GK-1 tube section would not work. I am going to be putting in a 1uF Platinum at C21 in the near future, but I have to make sure I have room for it first.
I too will soon be putting in BC560s, however the AudioCaps will have to wait as I know I don't have room for both of them and the Platinums.
-West
West,
I understand your desire to have a 1uf Platinum at the output cap, but you have to mount it off board and use long flying leads, which is not the best. I think the Auri-T teflon bypass on the stock Auricap 1uf will work just as good, if not better, and it's 70% less. I would have waited for pcX to get them in stock, but had the little Platinum cap so just went ahead and did that. On the other side of the interconnect is a .47uf Platinum at the amp input, so it all is a bit redundant anyway.
Best of Audio,
Steve
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yeah
in my pursuing the best possible structure for best sound , i "hate" to have the IC connect an output cap to an input cap it is like well you know, through two layers of rubber
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Ah, Kyrill,
Such a colorful, poignant metaphor, reminds us all of our young days.....
Hugh
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West,
I understand your desire to have a 1uf Platinum at the output cap, but you have to mount it off board and use long flying leads, which is not the best. I think the Auri-T teflon bypass on the stock Auricap 1uf will work just as good, if not better, and it's 70% less. I would have waited for pcX to get them in stock, but had the little Platinum cap so just went ahead and did that. On the other side of the interconnect is a .47uf Platinum at the amp input, so it all is a bit redundant anyway.
Best of Audio,
Steve
Not sure I agree with you, Steven.
I used a 1uF RelCap RTX as the output cap (C21) instead of the Hugh-supplied Auricap and it just sits there on the PCB. The teflon is probably a little larger but not by much.
Regards,
Andy
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why are in general long leads (especiall to caps?) things to avoid?
- they are longer antenna's so they pick up "lower" wavelengths EMI and RMI interference "closer" to audible spectrum?
- DC resistance moves up?
if you use shielded wires from caps to pcb, would that annul the effect?
if you use thicker wires from caps to pcb, would that annul the effect?
or is there something else? shielded wire sounds less "open"?
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If I were to put a Platinum at C21 I would have to have long leads, so maybe I will just bypass it. I was first considering to bypass, but then I thought I just might as well put the 1uF platinum in. I guess I will just go ahead and bypass and see how I like it. What value of Auri-T or Platinum should I use? .1uF or .01uF?
For C1, I do technically have long leads on the C1, but it is no longer than the wire that would have to be there anyways. I just have it from the Manual board connecting to the Analog board, but I guess for C21 I shall try and keep them short.
-West
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Kyrill,
Long leads are fine if they are shielded. But a large cap can be a sink for EMI, and there is some wisdom in shrouding it with metal to prevent ingress of EMI. Of course, caps are more sensitive at the input than they are at the output, where impedances are much lower as the signal has been strengthened.
Cheers,
Hugh
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West,
I understand your desire to have a 1uf Platinum at the output cap, but you have to mount it off board and use long flying leads, which is not the best. I think the Auri-T teflon bypass on the stock Auricap 1uf will work just as good, if not better, and it's 70% less. I would have waited for pcX to get them in stock, but had the little Platinum cap so just went ahead and did that. On the other side of the interconnect is a .47uf Platinum at the amp input, so it all is a bit redundant anyway.
Best of Audio,
Steve
Not sure I agree with you, Steven.
I used a 1uF RelCap RTX as the output cap (C21) instead of the Hugh-supplied Auricap and it just sits there on the PCB. The teflon is probably a little larger but not by much.
Regards,
Andy
Sure you can use a 1uf Rel RTX as it would fit nicely on the board. A 1uf teflon cap by anyone is HUGE and must be off board. I once had a Mundorf Silver/Oil as output cap, and it was large and off board. I eventually found another application for it. The RTX can also be bypassed by a small value teflon cap.
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If I were to put a Platinum at C21 I would have to have long leads, so maybe I will just bypass it. I was first considering to bypass, but then I thought I just might as well put the 1uF platinum in. I guess I will just go ahead and bypass and see how I like it. What value of Auri-T or Platinum should I use? .1uF or .01uF?
For C1, I do technically have long leads on the C1, but it is no longer than the wire that would have to be there anyways. I just have it from the Manual board connecting to the Analog board, but I guess for C21 I shall try and keep them short.
-West
The smallest Auri-T is .015uf. The smallest Platinum is .01uf. A .1uf cap would be difficult to use as a bypass cap as it's about twice the size of the 1uf Auricap.
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yeah
in my pursuing the best possible structure for best sound , i "hate" to have the IC connect an output cap to an input cap it is like well you know, through two layers of rubber
Yes this is true. One of the caps is redundant. As long as the system stays put, and no changes are really made, then an input cap could safely be removed. In my case the input cap on the amp is a bit redundant, and I've thought about taking it out. Maybe some day.
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Since I will be mounting these on the back of the board (my tube side, as the tubes come out of the case), I will be picking the .01uF Sonicap Gen II. It is only .18" in diameter, so its perfect to put on the board and it should fit when I close the case.
My only question is that since the cap is cheap, is there any benefit to have two .01uF per side, or will it be a minimal difference from just one per side, or will it have no difference?
Thanks
-West
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West,
If you want more bypass capacitance, merely buy one cap of 0.022uF. I'm pretty sure it's not much bigger, IF you can fit it in.
Cheers,
Hugh
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Since I will be mounting these on the back of the board (my tube side, as the tubes come out of the case), I will be picking the .01uF Sonicap Gen II. It is only .18" in diameter, so its perfect to put on the board and it should fit when I close the case.
My only question is that since the cap is cheap, is there any benefit to have two .01uF per side, or will it be a minimal difference from just one per side, or will it have no difference?
Thanks
-West
Are you using the Gen II's as bypasses? If you are going to bypass, the only ones really worth the trouble are teflons. And even then, it's a small to neglible improvement. It's mostly just part of one's personal stamp on the gear.
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hi musical sound lovers
I completely agree how important caps are in the sound path
but just as important and even more hearable is cleaning up the wall current
Felix did wonders for my SB3 and preamp
balanced transformers wonders for poweramps ( Aksa's and Jadis)
Just as important is damping or favourable colouring as some vibrations cannot be damped but be influenced ( C37 theorie)
would be nice if we from the Aspen school share our other approaches to virgin sound
:)
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Nah, guys - forget all this power BS! :lol:
To get good sound, all you need (as long as you have AKSA gear) is make up some aluminium pyramid frames. You need a big one (to fit over your listening chair) and then smaller ones for your AKSA / LF / GK-1. :thumb:
Trust me on this, guys! :lol:
Regards,
Andy
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Andy Andy Andy
If you have a machine to make a heavenly beer out of water
do you really think the quality of water would make no difference at all exept for
Joe sixpack?
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Andy
you are giving the image similar to Get Smart's 'cone of silence', and you are starting to worry me. :icon_lol:
T
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Hi Theo
how are your DEQX adventures going?
forgive me for "chatting" in this thread :oops:
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Well you know, I'm thinking I might just do something funny.
I am going to bypass them with .33uF V-Caps as they have the smallest diameter. They still won't fit, but since i used 3/4" MDF I will rout out little areas for them to sit. I feel this is the most economical and practical compromise. I don't have to deal with trying to fit huge 1uF caps in, and it costs less, but I have a feeling the difference in sound will be minimal.
-West
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Gidday from Cairns.
My GK1 has finaly died and I am going for a total rebuild.
I don't know if I can afford this wish list, but here is what I gather are the best possible upgrades: :drool:
C1 Sonicap Platinum 1uF
C4 & C7 Audiocap PPMF 40uf
C6 Oscon 47uF 20V ?
C11 + C12 Nichicon Gold Tune 100uF 63V ?
C10 + C14 Nichicon KZ 100uF 50V ?
C19 Sonicap Platinum .01uF
C21 Original 1uF Auricap bypassed with Sonicap Platinum .01uF
T1, T2, T4 BC560 (matched)
R5, R9, R11, R22, R26a, R26b. Riken Ohms, Vishay etc
I will be using my current DACT attenuator and DACT selector with Seimans 7308 Gold Pins.
Have I missed anything?
Mark
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Mark,
That's quite an impressive list you've got there! Your probably going to need quite a funky case setup to accommodate all those caps! I personally have TKD attenuator bypassed with Vishays, but I think the DACT will do just fine.
I can send some matched BC560s your way via the USPS if you would like. I've got a bunch left over from the group buy and the envelope is light enough that the cost of shipping to Australia is negligible. Shoot me a PM.
-West
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My GK1 has finaly died and I am going for a total rebuild.
I don't know if I can afford this wish list, but here is what I gather are the best possible upgrades: :drool:
C1 Sonicap Platinum 1uF
C4 & C7 Audiocap PPMF 40uf
C6 Oscon 47uF 20V ?
C11 + C12 Nichicon Gold Tune 100uF 63V ?
C10 + C14 Nichicon KZ 100uF 50V ?
C19 Sonicap Platinum .01uF
C21 Original 1uF Auricap bypassed with Sonicap Platinum .01uF
T1, T2, T4 BC560 (matched)
R5, R9, R11, R22, R26a, R26b. Riken Ohms, Vishay etc
Mark
"Missed it by that much!" :lol:
For C10, C11, C12 and C14, IMO use Black Gates - not Nichicon Gold Tunes.
For C6, I used a BG 25v 'PK' in place of an Oscon.
And for C21, use another Sonicap Platinum (or a Mundorf SiO) rather than the Auricap bypassed with a Sonicap Platinum .01uF.
And I would be careful about willy nilly substituting Riken Ohms. There was lots of discussion about these in early AKSA days (pre LF - so, mebbe 5 or 6 years ago?) and the general consensus was that these reses change their resistance minutely with the amount current going through them. This means they cause slight "tubey-like" distortion. So they may make your GK-1 slightly less "crisp"?
That being said, I personally did install Riken Ohms for the reses to the volume control. :D
Good luck. :thumb:
Andy
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Mark,
I personally have TKD attenuator bypassed with Vishays, but I think the DACT will do just fine.
-West
Given the history of how us GK1-cost-no-object types ended up with the TKD/Vishay option (ie. via the late and great Bob Crump and his search for the ultimate volume control), I sincerely doubt that the DACT comes within a bull's roar :lol: ... but given Mark thought he might have trouble coming up with the readies for the upgrade list he quoted, adding another USD370 (at least) for a TKD is unlikely! :D
Regards,
Andy
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...and when you don't know what your doing...the naked Vishays fall apart :duh: :duh:
-West
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Many years ago Hugh kindly let me be one of the prototype builders and the GK1 was my first soldering job of any kind. I have no idea how it lasted this long to start with. :thumb:
I am sure he just wanted to know if a klutz could build it!!!! All Hugh provided was the parts list, board, valves and valve holders. I found all other parts from various vendors in Oz. It worked as advertised. :scratch:
Anyway I digress. Far too much ReD wINe.
Since it died about 3 months ago, my wife has even allowed me to fix it, as my very old Musical Fidelity Synthesis is just not up to the job.
Just after I built the GK1 I aslo built Hugh's phono stage and some how used 1W 5% carbon resistors. I think the originals where not working or something and Hugh suggested a different value and all I could get where these cheepies form Jaycar.
Anyway, I was floored by the transparity and lack of noise from the el-cheepos so I will be using the same in the new GK1.
Now for the details:
Case, no problem, I build from wood and the case will be what it ends up. I am also finally going to put the N+ upgrade into the 55 so I just might make a floor standing amp case totally of local hardwood so it becomes a piece of furniture.
Mods to a 55 N+ are also accepted :thumb:
Cost is as always a problem, but I will try and do the most cost effective and anyway, tax return time is 2 months away so..........or lotto....... or kill the w&%e....... or kill the k%^s...... or mother*&!aw aa
Mark
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Mark,
For the 55N+, go for Hugh's new power supply design as used on the latest Amps. The difference isn't subtle!
For the GK-1, I'd use Nichicon KZs at C10, C11, C12 and C14, to my ears they sound more "Effortless" than BGs.
Cheers,
Ron.
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Mark,
For the 55N+, go for Hugh's new power supply design as used on the latest Amps. The difference isn't subtle!
Hi Ron
Is there an upgrade available for the 55N+ power supply or are you talking about buying the Lifeforce amp?
Tim
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Case, no problem, I build from wood and the case will be what it ends up. I am also finally going to put the N+ upgrade into the 55 so I just might make a floor standing amp case totally of local hardwood so it becomes a piece of furniture.
Mark....this is fast becoming my re-casing option. A floorstanding arrangement with the amp, pre-amp & DAC built in to the casework, shelf space for the CD and the top being available for the vinyl thingy. I am also thunking/dreaming about a panel PC & storage to manage a software library for outout to the DAC.....
....and I'm thinking about a really original name for it like.....phonogram....except I have this vague idea it has been used before :?
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Gidday from Cairns.
My GK1 has finaly died and I am going for a total rebuild.
I don't know if I can afford this wish list, but here is what I gather are the best possible upgrades: :drool:
C1 Sonicap Platinum 1uF
C4 & C7 Audiocap PPMF 40uf
C6 Oscon 47uF 20V ?
C11 + C12 Nichicon Gold Tune 100uF 63V ?
C10 + C14 Nichicon KZ 100uF 50V ?
C19 Sonicap Platinum .01uF
C21 Original 1uF Auricap bypassed with Sonicap Platinum .01uF
T1, T2, T4 BC560 (matched)
R5, R9, R11, R22, R26a, R26b. Riken Ohms, Vishay etc
I will be using my current DACT attenuator and DACT selector with Seimans 7308 Gold Pins.
Have I missed anything?
Mark
Mark,
Well, first of all you gotta fix what broke first, and I'm sure you're covered there.
I don't have too many stock parts in my GK-1. The list must be somewhere here on the thread.
BUT, when it was all said and done, I tend to think that the only things that made real differences have been the Platinum cap at C1 and the 7308 tubes. You've already got the tubes. A good and cheaper alternative for C1 is .47uf Mundorf Silver/Oil.
You can change all the other stuff, just because you can. Afterall, ALL parts are user serviceable.
Have you thought about having the wire from the output pin TO the rca be the same as what you use for the interconnect cable FROM the rca to the amp? It's the same signal, and I like to make these as similar as possible.
Steve
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Hi Steve, yes, I already do the cable that way - all done with Teflon Cat5 strands.
Mark
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Tim,
I think Hugh will provide you with the PSU upgrade separately if you talk to him nicely :wink:.
Cheers,
Ron
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Thanks Ron,
How are things? I hope you and the family are well.... I will send you an email!
Hi Tim,
The upgrade to the power supply on the 55 is restricted to Nichicon Gold caps. The upgrade I believe Ron refers to is for the higher voltage and capacity demand of the LF100 and subsequent amps with 50V rails. It will work with the 55, but is not sold for them specifically.
Cheers,
Hugh
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At the moment i don't use my GK1 anymore. It's a complete version with remote control and input board.
The GK1 has some of the modifications written in this threads. A marvelous pre-amp. The best and most musical i ever had.
If someone is interested to take it over, send me an PM
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At the moment i don't use my GK1 anymore. It's a complete version with remote control and input board.
The GK1 has some of the modifications written in this threads. A marvelous pre-amp. The best and most musical i ever had.
If someone is interested to take it over, send me an PM
??? So, hybride, if it's "the best and most musical (preamp) I ever had" why are you no longer using it? :)
Regards,
Andy
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Hi Andy.
Less is more, i believe. But sometimes that rule doesn't bring the best. My beloved TDA1541 DAC project always needed a pre-amp to get a full body sound. Without pre it sounded 'thin' in de mids and the lows. We did more modifications in the output stage of the DAC. Now the DAC sounds better with direct coupling to my LF100 amp. There is a little more resolution with direct coupling, but, i have to admit that with the Pre there is some beter 3d presentation. While i only use the DAC as source, i have decided to go on without pre.
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Hi Andy.
Less is more, i believe. But sometimes that rule doesn't bring the best. My beloved TDA1541 DAC project always needed a pre-amp to get a full body sound. Without pre it sounded 'thin' in de mids and the lows. We did more modifications in the output stage of the DAC. Now the DAC sounds better with direct coupling to my LF100 amp. There is a little more resolution with direct coupling, but, i have to admit that with the Pre there is some beter 3d presentation. While i only use the DAC as source, i have decided to go on without pre.
Different strokes ... as they say! :D
I have 3 sources but I also like the result of the tube output stage in my GK-1R with my LF amps. :D
Regards,
Andy
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West,
I strongly support Steve's POV here; the only cap that really seems to make a difference is the input cap, C1, though the output coupler (the yellow Auricap) will have a discenible effect but can simply be enhanced with a teflon bypass, say 0.1uF.
That input cap is VERY influential, as an appreciable AC current does pass through it. The interstage coupler, C19, drives only a tube grid, and passes no current. The polystyrene supplied is a very good cap, tiny too, and can't much be improved upon.
The GK1 as it stands is capable of extraordinarily high performance sonically, out of all proportion to its relative simplicity, and I have been trying for six years to improve on this circuit with very little success.
Hope this helps, and thanks Steve for your input,
Cheers,
Hugh
Hi Hugh,
Never know where I'll pop up. heheh, so could you then eliminate C19, and have the stages direct coupled?
Ray Bronk
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Hi,
Hugh, if the tantalum works that means I have to change my board from ugly to colorful. Aren't the tantalum usually colored in pastel? I don't have any tantalum to compare to the Solens. Can't wait to hear from others on how amazing this change is.
Cheers,
Philip
Hey Philip,
What were the original values of the caps on C4 and C7? Also, you said you changed some resistor values?
Andy, if the original values were smaller than the 47UF, (yep, big caps) that in itself would explain the difference in sound.
Ray Bronk
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Hi Mark,
Possibly, but I have to be damn sure it betters the original design.
That said, I ALWAYS check these things. And I have a few ideas of my own, nuttin' stands still......
'We pursue a policy of continuous improvement, and make no apology for it, so there...... :deadhorse: :hyper: :banana piano:'
Hugh
Ah another perfectionist, just like myself.
So what do these changes actually do. What is the purpose of the LED? also the change in resistors what do they do?
* Use the LED from L1 in the C4 position.
* In the spot where the LED was [L1], use a cap. [I presume this is where Philip has used the Solen since he's also using the "ginger LED mod".]
* Change R13 to 470 ohm
* Change R14 to 10 kohm.
Ray Bronk
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But Darren,
Do you really need 200w into 8 ohms to power your speakers ... given that you've got a sub and so I suppose have rolled off the low end? :D
Regards,
Andy
I didn't really need the worked V8 I had 20 years ago either ... but I still miss it. :wink:
True, my speakers are an easy load though only 83db or so .... but if I could have double the power without giving anything up ... :drool:
Besides that first watt, more power means to drive the speakers with less stress or effort, thus providing more sound goodness.
Ray Bronk
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more power means to drive the speakers with less stress or effort, thus providing more sound goodness.
Ray Bronk
I would have expressed it slightly differently. One's power requirement is driven by 2 factors:
1. How much RMS power you need to drive the speakers to the dB level you listen at.
2. How much headroom you believe is required, to faithfully deliver the leading edge of transients.
Re. 1: Obviously, if you have very inefficient speakers, this will be many times what, say, horns require. :) So we could be talking about (RMS) 50 watts instead of 2 watts. :o
Re. 2: Some people proclaim that all you need to allow for is 6dB headroom ... however, I read somewhere that to faithfully reproduce the sound of someone tearing a piece of paper takes 1,000w! :o
This issue is complicated by the fact that it's the instantaneous power delivery which is the crucial factor - not the RMS rating. Obviously, a 100w amp which is only being run at 2w (at the required listening level) because the speakers are very efficient, will have plenty of headroom ... but so will a 50w amp whose PS has been configured to deliver 500w over 1/10th of a second. :D
Regards,
Andy
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I would have expressed it slightly differently. One's power requirement is driven by 2 factors:
1. How much RMS power you need to drive the speakers to the dB level you listen at.
2. How much headroom you believe is required, to faithfully deliver the leading edge of transients.
Re. 1: Obviously, if you have very inefficient speakers, this will be many times what, say, horns require. :) So we could be talking about (RMS) 50 watts instead of 2 watts. :o
Re. 2: Some people proclaim that all you need to allow for is 6dB headroom ... however, I read somewhere that to faithfully reproduce the sound of someone tearing a piece of paper takes 1,000w! :o
This issue is complicated by the fact that it's the instantaneous power delivery which is the crucial factor - not the RMS rating. Obviously, a 100w amp which is only being run at 2w (at the required listening level) because the speakers are very efficient, will have plenty of headroom ... but so will a 50w amp whose PS has been configured to deliver 500w over 1/10th of a second. :D
Regards,
Andy
Hi Andy,
Well, I wasn't intending to be technical. In theory, you double the power/wattage, and you only get a 3DB increase in sound. Of course, what you said also applies. Bob Carver was once to have said, "in order to reproduce a fingernail scratching a blackboard, it takes about 500 watts to correctly reproduce this sound." Now, before you hold me to that exact statement, it was an approximate quote. There's other factors, such as the bandwidth of the amplifier in question. Now, I am not an EE, and I certainly don't pretend to be, so I'll let Hugh chime in on this subject. But if we take this any further then we need to put this in another thread.
I have to say, reading this thread for the past several hours was a most delightful time. Frankly, the other circles could learn from this one thread in how to conduct themselves. This is a testament to all the participants here in this thread. i thank you. So now when I get rich, and eventually get my GK1 and Naksa, and maybe the Vsonics, I'll be able to enjoy some real goood stuff for a long long time. Thank you again.
Ray Bronk