AudioCircle
Audio/Video Gear and Systems => Tube-o-phile Circle => Topic started by: 2bigears on 8 Jun 2014, 01:54 am
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:D Hi everyone. Can somebody help with an amp selection please and thanks. Right now I have the KW750 by Mus Fid.....
The Pre is VAC Ren Sig.
The speakers are Proac D-38's
Would like a tube amp with enough juice to drive the 38's yet make them sing sweetly.
the big Mus Fid is good ,, but if anyone knows a good match to streamline my system,, as I would like a one box amp
I think tube amps have come a long , long way and really don't know any good ones that would fit the system.
As usual,, thanks for any thoughts or ideas.... Pat up in cold Canada .... Good Lord will it ever warm up ????? :D
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:D Hi everyone. Can somebody help with an amp selection please and thanks. Right now I have the KW750 by Mus Fid.....
The Pre is VAC Ren Sig.
The speakers are Proac D-38's
Would like a tube amp with enough juice to drive the 38's yet make them sing sweetly.
the big Mus Fid is good ,, but if anyone knows a good match to streamline my system,, as I would like a one box amp
I think tube amps have come a long , long way and really don't know any good ones that would fit the system.
As usual,, thanks for any thoughts or ideas.... Pat up in cold Canada .... Good Lord will it ever warm up ????? :D
Hi 2bigears.
Come on planet Vietnam for a month or two and then go back to Canada (My home country)
then you will stop complaining/mentioning about the cold. :lol:
Guy 13
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I would suggest Bryston B100(used) or the new B135.
They are dual mono in one box, yet are simple in the output circuit, use just one pair of transistors.
If you mean say a tube amp: It could be a BAT 55 as the D39 is 4 ohms and only 91dB sensitivity.
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Well, in Cold Lake it is SUPPOSED to be cold man !!! I hear some of the poor folks over in Manitoba are having to crank their AC and many water lines are still frozne , crazy stuff
-jay
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Frozen stuff ,,, in June ?
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:D. Serious boys and gals ,, I need a good tube amp that will fit ,,
My last one ,, Ha :D
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A VAC would match nicely with your pre. How do you think it would mate with your speaks?
What about a Music Reference RM-200?
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:D yes, it seems logical a big 300 would fit nice. I was just wondering if you have to spend that much
These days with the advanced tube amps. It seems value is really good. I could be wrong. :D
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I'm very happy with my Stereo 100:
http://rogueaudio.com/Products_100.htm
It's fast and powerful, which is what I think you're after when you say 'tube amps have come a long way...'. The Music Reference RM200 is probably the better amp but it more expensive at $4,900+:
http://www.ramlabs-musicreference.com/music_reference_rm-200_hybrid_power_tube_amplifer.html
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750 Watts per channel isn't enough? Really?! Or are you saying the MF isn't a good match due to other factors?
As far a VAC amp (or monoblocks) you needn't buy the latest or newest, I bought a pair of older VAC PA-160 monoblocks and have been very happy with them. Paired with a VAC CPA-1 with upgrades from VAC I haven't been looking for electronics for quite some time. I'm a firm believer in single mfr. synergy when it comes to electronics.
That said, I think you'll be looking at the big tube amp brands such as VTL, Audio Research, McIntosh, Rogue, maybe even Atma-Sphere. Do your homework and you will find what you need (with a little help from your friends). Atma-Sphere amps may require the autoformer between the amp and speakers which basically makes them into an amp with output trannies. Never made sense to me to do that, one should use speakers that work well with OTL designs.
Just my .02.
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:D. It's not a power thing. It's just I'm trimming the size and therefore rack space.
I'd like a tube amp in a one unit config. The 750 has two units. It's a good amp
With major headroom. The VAC pre is a keeper as its phono is well done.
I just was wondering if any modern tube amp would fit right in. I am a true
believer value has gone up with technological gains and better designs.
I could be wrong. :D
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Frozen stuff ,,, in June ?
Yup, think things are getting better now but as of May 31, there were still a lot of folks in Winnepeg withot water. I heard there was frost 8' in the ground in some areas, long cold winter there this year
Sorry for the OT info guys
-jay
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:D this Canadian winter was very cold for long stretches..... A bad one. El Niño is to return next winter....
I hope those meteoroligists are right for a chance,,,,, :D
Are those Rouge amps good ones ? Haven't heard much about them. :D
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:D. VTL 450 Sigs 11 on eBay for 6800 bucks. Might be overkill ?
Don't know much about VTL,, but mono blocks and lots of tubes kinda just means more $$$$. :D
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Rogue Cronus Magnum with KT120's. Roll in some vintage 12au7 and 12ax7's to your sonic preferences after everything has broken in.
Built like a tank, built in the USA, incredible customer service, sounds wonderful and looks good doing it. Outstanding value, you'll have money left over for other things.
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:). I have a pre I will keep till I pass this world..
I'm looking to go from a SS to tube amp,, 1 box with upper performance.
Aren't we all,, ha I play old rock and nothing else. Just the good stuff. Vinyl and Apple dig.
Will give up 1.1kw's of power as I really over bought with the 750.. But it's a cool amp.. :D
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For your "very" last amp ever, take a look at the new Convergent Audio Technologies
JL5.
100WPC and around 12K list.
Ken Steven's best bang for the buck ever.......
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:D I'm thinkin' I love the last amp talk,,,, but 12k is kinda getting up there.. I will have a look.
Art has his VAC 300 up for 9k.... even that seems a lot.. think there is still a bargain amp out there somewhere.
hummmm..... what to do ?? :D
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Oops the BAT 55 not a good idea: all in PCBs, too much stress in the output tubes and expensive.
Instead see the Audio Mirror 45W: all in point to point Silver wire.
http://www.audiomirror.com/amps.html
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The Rogue Stereo 100 is new so there's only 1 review so far:
http://www.positive-feedback.com/Issue70/rogue_st100.htm
...but there are tons of reviews of other Rogue amps out there. You can get a feel for the sound of the company by reading them. The Cronus is sonically more of a traditional tube amp compared to Rogue's other models. Not sure that's where you want to go. It is a fine amp, however.
Here's a review of the Music Reference ($5,900 version with custom trannies):
http://www.stereophile.com/content/music-reference-rm-200-mkii-power-amplifier
Be sure to read Atkinson's testing notes where he waxes poetic about this amp.
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:D those look like 2 really good candidates .. One at 3 and one at 6 large. Two very interesting
amps indeed. Time to do a little reading on these guys. Are the ARC's worth a look ?
Something like the 150 Ref ,,,, or is that gear over priced ? :D
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Check out Decware mono amps. Lots of fans out there....chime in.
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Quicksilver Silver 88's or V4's if you need 100+ tube watts.
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:D. The 38's are 91eff. So will those Decware amps work ? They look pretty dam sweet.
I have heard the Quicksilvers work good with the Proacs too. Paradox of Choice ---- again. :D
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The only 1 box Quicksilvers are the original MS 190 and the GLA.
My speaks are 91.5 db efficient and I get great volume out of my 35 watt GLA. But I *think* you're looking for a faster, 'newer' tube sound. Quickies are a little closer to traditional tube amp sound than my other recs.
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:D. I've sent Steve an inquiry on which amp he would recommend.
These push pulls are powerful little beasts I assume. 35 or 55 watts
don't sound like much. And I do listen to old rock mostly cause I'm old as dirt.
Fast and yet detailed is what we ll look. For ,,? No ? :D
Thanks for the reply guys..... I muchly appreciate .. :D
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Given what has been written here, I would at least look into a Harmon Karkon Citation II with the Jim McShane mods. Those amps have some amazing sonics. They have all the tube goodness, ultra wide bandwidth, and pretty fast sounding for tubes.
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:D. Harmon ?? Those are not in the same boat,, I could be wrong. :D
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:D . Harmon ?? Those are not in the same boat,, I could be wrong. :D
A properly restored Citation II is one of the very best sounding power amps ever made. The output transformers are good from 5 Hz to 80 KHz (you won't find that from most any modern iron). They are not your typical sounding tube amps. They have a fast and detailed sound with a great 3D sound-stage.
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:D. With total respect, it's no the amp I want to live with for the next 10 years .. :D
Decware has caught my eyes. Steve can set me straight tomorrow on his workings.
Those amps look inviting to say the least. :D And I've always loved "make it on your own
companies rich with smarts and ambition to warrantee a product for life" . Talk about stand
behind your work. :D As always,, I could be wrong.. What do I know ? :D
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No worries. This hobby is all about "horses for courses". What works well for some people does not work for others.
Home audition is very important to decide what works in your system. All things being equal, unless one has very sensitive speakers (over 100 db/w) more power is almost always easier to get good sound from.
Here is a pic of my tube amps:
(http://www.audiocircle.com/image.php?id=100834)
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:D. That Zen Mystery Amp looks interesting as an amp can.
Is 40w good enough power for 91db ?
And how long is their build time ,, ? :D
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:D . That Zen Mystery Amp looks interesting as an amp can.
Is 40w good enough power for 91db ?
And how long is their build time ,, ? :D
Thee short answer is "it depends". As long as your listening level is low to moderate, may work out nicely. Would recommend you audition a 40 watt tube amp with your speakers to see how you like it. I had 91 db/w speakers with a 40 watt tube amp, and it turned out that 60 watts of tube power was required to get it right.
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Given what has been written here, I would at least look into a Harmon Karkon Citation II with the Jim McShane mods. Those amps have some amazing sonics. They have all the tube goodness, ultra wide bandwidth, and pretty fast sounding for tubes.
I don't always agree with Freo but I totally agree with his suggestion this time. I'd take a pair of Mcshane's Citation amps over anything Decware has ever produced. The Citations are amazing. I heard Jim's at his house years ago and was amazed. Beautiful sounding amps.
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Hi Pat!
Smart move going after tubes to help keep the place warm. :D
I'm not sure of your budget, but you may want to consider these:
http://app.audiogon.com/listings/tube-rogue-audio-m-180-mono-blocks-2014-05-17-amplifiers-20774-upper-marlboro-md (http://app.audiogon.com/listings/tube-rogue-audio-m-180-mono-blocks-2014-05-17-amplifiers-20774-upper-marlboro-md)
Have fun,
Jerry
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:D. Those monos are a good buy ,, but I was wondering if I could stick
to 1 box. The price is good on them too as used gear is a buy.
Paradox of choice ! Dam :D
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Why not a Conrad Johnson? You can get these from $1500 to the sky's the limit. A Premier 11 @ around $1500 would be a great first tube amp. The classic 60 has been on stereophile's recommended list for ever as well. Even powerful 140wpc ones like the Premier 140 you see asking price of $3500 on audiogon. I'd take a CJ over an ARC and many other tube amps in a heartbeat. Not the flavor of the month tube amp, just something with solid construction and sound quality that you can listen to forever.
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The only 1 box Quicksilvers are the original MS 190 and the GLA.
My speaks are 91.5 db efficient and I get great volume out of my 35 watt GLA. But I *think* you're looking for a faster, 'newer' tube sound. Quickies are a little closer to traditional tube amp sound than my other recs.
With his diet of old rock, a little forgiveness would probably be welcome on most of those recordings. I have a friend with V4's and I've found them to be quite involving and well voiced. Plus you've got a boatload of tube rolling possibilities to tune to your taste.
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:D Everbody needs forgiveness. I do play very good vinyl on a pretty good table.
And my dig is not terrible. But we all need a little forgiveness and I think tubes
help. :D Too many dam amps to choose from. My head is going to frickin' explode. :duh:
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:D. Question for you amp guys ,, would the quicksilver V4's power my D38's ? Some for sale down in
NY area. I have heard rumours these are good pieces ? :D
Reading the add again,, they are mono's of course ,, and 'unbalanced' which I don't know
what that even means ? :D
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V4s would power the D38s, as well as conrad-johnson Premier 11.
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:D ok, thanks. Ill call NJ .... :D
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:D. Question for you amp guys ,, would the quicksilver V4's power my D38's ? Some for sale down in
NY area. I have heard rumours these are good pieces ? :D
Reading the add again,, they are mono's of course ,, and 'unbalanced' which I don't know
what that even means ? :D
Unbalanced means RCA inputs only. No XLR inputs.
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:D. Question for you amp guys ,, would the quicksilver V4's power my D38's ? Some for sale down in
NY area. I have heard rumours these are good pieces ? :D
Reading the add again,, they are mono's of course ,, and 'unbalanced' which I don't know
what that even means ? :D
The V4's would power the D38's with ease / headroom to spare. They now ship with KT 150's and are rated at 170 watts per channel. I don't know if this is a drop in for the older V4's or not. Regardless, it's rated at 120 per channel with KT 88's. Still all the power you'd ever need.
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If you love the pre, I say stick with Kevin's stuff. I say go for a 300.1.
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:D. Well darn. The V4's are cheap to buy, sub 5k. A 300.1 is ten. Ahhhhh , I was trying to save loot in these lean times and crazy times to come. I guess you can't fool the pipper. Buck up. Dam this hobby. :D
I was trying to go for a modern design that's easy on tubes and cheaper to buy because of techno
advances. Maybe I'm chasing a ghost. :D
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I say go for a 300.1 !!!! :D
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:D. Art,, are we a little biased ? Ha. I hear you brother ! I hear you ! :D
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I say go for a 300.1 !!!! :D
What Art said 8)
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The Music Reference RM200 is probably the better amp but it more expensive at $4,900+:
http://www.ramlabs-musicreference.com/music_reference_rm-200_hybrid_power_tube_amplifer.html
I recently got hold of an RM-200II-T and it has been working great in my system: Daedalus DA1-1 speakers and Modwright LS-100 preamp. The Daedalus speakers are pretty efficient at 94-95dB but have plenty of large drivers to move. The RM-200II is delivering 100wpc with only 4 output tubes and 2 drivers. It is probably overkill for my needs but I appreciate the extra power.
Make sure you do a lot of research and reading opinions of owners for all of these amps, whether it be Music Reference, Decware, Rogue, etc.
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Gulp! $900 just for a bal connection woow.
Unbalanced input refer to the input connection, RCA connector which is the usual and recommended in a tube amp.
XLR 3 pins balanced input (with a proper mini transformer) are rare and unusual, I would dint take it.
I never listen this amp, but it seems good reading the spec on the manufacturer site cause:
- Good weight 51 lbs if it is for each mono amp, if both amps weight 51lbs dont buy it.
- Point to point wiring.]
Except for the astonishing price $6500 due the TAS magazine bliss.
Surely must be a better value on the market.
Other item call my attention is sheer power, this amp is too powerful.
Maybe with EL34 tubes it can delivery a few of small details, of course not as a SET.
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I wonder if the KT150 will be approved for use in any of the Rogue amps?
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2bigears,
Just gotta throw another .02 in the pot.
You have a VAC preamp that you say is the preamp until you pass from this world. I can damn near guarantee you won't get a better pairing for it than Art's VAC Phi 300.1, if you can swing the dosh. I will also pretty much guarantee it will be the last amp you buy. That's the opinion of another happy VAC owner who also has no plans to sell his VAC gear. Unless I win the lotto and decide to go up the VAC line. Also I agree Kevin designs excellent phono sections and I am a big fan of built-in phono stages in my preamps.
Also Art is a stand up person to deal with, again speaking from experience.
Jake
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I wonder if the KT150 will be approved for use in any of the Rogue amps?
According to Mark O'Brien, the KT150 can not be used in the Cronus Magnum where there are issues with the tubes being too close to some capacitors and insufficiency of the transformers. IIRC there are similar issues with at least some of the other Rogue amps.
He is having transformers made to experiment with the KT150s however, and may have some thoughts to share at the end of this year.
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ARC amps have always sounded greyish to me but I haven't heard their new KT120 versions. VTL, I'm not really familiar with.
I wasn't impressed with the old Rogue 120s but I liked their Stereo 90, love my Cronus Magnum (slightly modified by Rogue with Mundorf Evo Silver/Gold/Oil coupling caps replacing the stock and bypass caps) and was blown away by the Apollo mono-blocks (with the Hera pre) running KT120s.
As much as I have always really liked Conrad Johnson amps, I don't think they are great for rock. (I've owned a MV60, later upgraded to the SE, had in my system an LP66S for an extended period, and listened extensively to LP140Ms.) They leaned a touch to the mid-range and highs and lacked a little bit of propulsiveness (though I'd love to hear their new KT120 based amps). Due, at least in part, I think, to the use of 6550s: KT88s (and now KT120s) just seem to have more bass.
But most KT88s based amps I've heard seemed to have too much bass emphasis for music other than rock (including a pair of Quicksilver Mono 100s I owned - the V4s I heard at a show did not seem to exhibit this issue however). The one consistent exception to this rule has been VAC: the several amps of theirs I've heard have been the most linear, harmonically accurate and beautiful tube amps I've ever heard.
As has been mentioned, however good an amp may be, synergy with the whole system - particularly the pre-amp - is crucial. Obviously with your VAC pre, this would not be a concern with a VAC amp. And as glorious as the 300.1 rooted for above would be, there are the less expensive options of a Phi 200 or an older Phi 110/110. There is also the option of going for a VAC integrated such as the Sigma 160 or the older Phi Beta 110 (may take a while to find any VAC used though).
Alright, I better stop: I'm :drool: now.
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I have not seen it mentioned in this thread that the KT-150 is not a drop in replacement for KT-88 and KT-120 amps. Besides the filament current being as high as 2 amps, it appears at first glance to have higher transconductance than the typical KT-88 which may cause some amps to be unstable. It also appears to want a lower negative grid voltage which may be out of the range of some bias pots.
Here is the data sheet. http://www.tubeampdoctor.com/images/File/data%20sheet%20KT150%20Tung-Sol.pdf
Also, keep in mind that the power of most tube amps is not limited by the tube but by the parameters of the circuit. These will not change therefore dont expect any significant increase in power. It will provide more power in a circuit designed to take advantage of its higher dissipation and plate current. However, those circuits may not be backwards compatible with the KT-88 and KT-120 especially if they are designed with the high screen voltage (650 V) that is part of the draw for this tube in ultralinear circuits.
A question to the member who started this thread. How much power do you really think you need for a 91.5 db/watt speaker? I would be using about 1 watt.
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How much power do you really think you need for a 91.5 db/watt speaker? I would be using about 1 watt.
Since the OP asked for amp suggestions, please elaborate on the 1 watt amp you'd prefer. :thumb:
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:D. Question for you amp guys ,, would the quicksilver V4's power my D38's ? Some for sale down in
NY area. I have heard rumours these are good pieces ? :D
Reading the add again,, they are mono's of course ,, and 'unbalanced' which I don't know
what that even means ? :D
I would stay away from Quicksilver amps, from my own experience, he cannot maintain/repair his older units. Once his amps get in need of repair, it's over. Been down that road and not going back. FWIW.
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I would stay away from Quicksilver amps, from my own experience, he cannot maintain/repair his older units. Once his amps get in need of repair, it's over. Been down that road and not going back. FWIW.
Can you elaborate? I thought all Quicksilver amps were point to point wired, which should make them easy to repair.
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I have not seen it mentioned in this thread that the KT-150 is not a drop in replacement for KT-88 and KT-120 amps. Besides the filament current being as high as 2 amps, it appears at first glance to have higher transconductance than the typical KT-88 which may cause some amps to be unstable. It also appears to want a lower negative grid voltage which may be out of the range of some bias pots.
Here is the data sheet. http://www.tubeampdoctor.com/images/File/data%20sheet%20KT150%20Tung-Sol.pdf
Also, keep in mind that the power of most tube amps is not limited by the tube but by the parameters of the circuit. These will not change therefore dont expect any significant increase in power. It will provide more power in a circuit designed to take advantage of its higher dissipation and plate current. However, those circuits may not be backwards compatible with the KT-88 and KT-120 especially if they are designed with the high screen voltage (650 V) that is part of the draw for this tube in ultralinear circuits.
Yes, this jogs my memory. Mark O'Brien also did mention there are major circuitry differences.
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I would stay away from Quicksilver amps, from my own experience, he cannot maintain/repair his older units. Once his amps get in need of repair, it's over. Been down that road and not going back. FWIW.
In the late 1990s I remember Tamara Baker do a comment in TAS, there was a issue on a tested amp and some opinions about a model from this brand.
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I just want the set of amps Freo-1 has (1625s that do 110 watts). Where can you get those?
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:D. Thanks for all the chimes guys. I do think its perfectly clear what I need to do. Dam !
:D
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I just want the set of amps Freo-1 has (1625s that do 110 watts). Where can you get those?
I can make you a pair of monos or a stereo. I've been working with that tube since I was 16 year old. I made a AM radio transmitter with a 5 mile range with one. Send me a message if you want one.
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Since the OP asked for amp suggestions, please elaborate on the 1 watt amp you'd prefer. :thumb:
I would recommend my RM-10 or my new 4 tube OTL. http://www.audiocircle.com/index.php?topic=121659.0
The power needed is more a matter of the listener. I rarely listen above 80 dB 90 dB peak so I would never even reach a watt with that speaker. However when I visited several listeners in the bay area I found they listened much louder than me, constantly hitting 99 dB peaks. Those levels hurt my ears!
There are excellent SPL meter applications for cell phones. I have one that shows peak and average. It's a lot better than guessing and fun to watch. There are also spectrum displays.
I really don't understand why the majority of these recommendations are for large amps when the post concerns a 91 dB speaker. And, why has no one asked how loud the listener likes his music and how far he sits from the speaker? So I am asking.
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:D. Right on the money. I love it. Like trying to go to a Doctor and the Doc asks no questions of how you eat or are you sleeping well. I do listen loudly on occasion and I sit about 8 feet from the speakers. And like before , nothing but old time rock and roll with can be very dynamic. Guitars of Pink Floyd to Ladies vocals. It's our North American culture that we like headroom. We think that more is better. I'm a prime example at 1.1KW's @ 4 ohms. I think that's what my SS amp is. It's crazy anyway. Tube amps are a different animal to be sure. :D
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:D. Right on the money. I love it. Like trying to go to a Doctor and the Doc asks no questions of how you eat or are you sleeping well. I do listen loudly on occasion and I sit about 8 feet from the speakers. And like before , nothing but old time rock and roll with can be very dynamic. Guitars of Pink Floyd to Ladies vocals. It's our North American culture that we like headroom. We think that more is better. I'm a prime example at 1.1KW's @ 4 ohms. I think that's what my SS amp is. It's crazy anyway. Tube amps are a different animal to be sure. :D
Thanks for your response. You really should try a lower power tube amp if you care about reproducing the excellent midrange (which no one has talked about) that you speaker is known to have.
Other than myself and Nelson Pass not many designers come out and tell you what has to be done in designing a high power amplifier. If one is designing for 10-20 watts it is easy to bias the amp in class A whether it be tube or SS. It is not easy or economical to make a 100 watt or larger class A amp. Excessive headroom is a misconception unless you are talking about single ended tube amps, and even then it's not the issue.
The common reply I get on the headroom question is that listeners think that 100x or 1000x headroom controls the speaker better. Well that's not what controls a speaker. Damping and the ability to deliver current controls a speaker. The Asmasphere was mentioned. It is a fine amplifier for what is can do but it cannot control a speaker no matter how big of one you get because it has very low damping and is current limited. No OTL I know of is suitable for a 4 ohm speaker unless it has a good autotransformer. BTW an autotransformer is quite different from a typical tube output transformer. It has much better bandwidth (mine is 200 KHz vs 60 KHz for a good Push pull transformer) lower losses and better bottom end.
If I may throw out a few numbers for consideration. If one makes a SS amp that produces 30 watts one can use high current transistors and bias them high without producing a lot of heat. Lower voltage transistors can handle much more current than high voltage transistors. A 30 watt amp needs only 25 volt rails for 8 ohms and less than 20 volts for 4 ohms. Transistors are very happy at those voltages. Your amp has about 100 volt rails. When you play music at 1 watt peak that's just 2 volts on the speaker and 98 volts on your transistors at half an amp which is 49 watts on the transistors. On a 20 volt rail amplifier its only 18 volts on the transistors at half an amp or 9 watts. I assure the transistors are much happier at 9 watts than 49 watts. Go up to a few watts and the numbers get rapidly worse for the big amp while getting better for the smaller one. The numbers only get good for the big amp at full power which you will never reach.
With all respect to SS amp designers they have one other big problem which is current delivery and short circuit protection. Now that we know (and I hope you believe me) that current and damping are important, what has to be done to protect the more fragile high voltage transistors? It turns out that at voltages over 30 V all bipolar transistors have a second breakdown region that limits their current to very low levels. That is why high power amps have so many output transistors in parallel (which is not good for midrange detail). One has to protect these from shorted speaker leads so there is current limiting. Unfortunately this current limiting is also looking at the voltage it is putting on your speaker and puts out less current at low voltages which is precisely what we don't want. High power amplifiers like to be used at high power and have significant problems driving difficult loads at low power. Because of their current limiting few of them can drive electrostats or any speaker with a reactive load. Reactive loads look like shorts to load line current limiters.
The downside of power headroom is that most large amps don't sound so great at one watt because of what the designer had to do to make a high power amp. Thanks to Nelson for naming his work "First Watt". So much of the detail of music is in that first watt. When one gets a really clean system going I find that listeners actually turn the volume down because now they hear all the music without having to turn it up. There are speakers out there with very low sensitivity that need big amps, but your speaker is not one of them.
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Just ordered PrimaLuna Dialogue Premium integrated from Upscale Audio. Stereophile class A rated, lots of tube related safeguards, auto-bias extends tube life), rolls EL34, KT88, KT120, etc., 32 - 43 wpc at 8 ohms, MSRP $3400. I have similarly rated speakers, so I'll let you know how it works out in a few weeks. PrimaLuna also sells power amp version that can be used in stereo or monoblock mode and a HP version with double the number of output tubes (from 4 to 8). Check out the reviews.
The old adage is that tube watts equal double the number of solid state watts. I'm an old fart and listen like one (to mostly small ensemble classical/jazz) but like a occasional Led Zeppelin sort of fix. Am a firm believer in amps maintaining a commanding grip on the speakers (lots of headroom) for improved resolution and driver safety. Have used 7 wpc, 40 wpc, and now 100 wpc solid state on these speakers. The 7 wpc did an amazingly respectable job but moving up to the 40 wpc turned the speakers from polite dinner guests into NFL linebackers in tuxedos. The 100 wpc hasn't added much.
Keep in mind that watts versus dB's is a logrthymic relationship, so doubling the power only adds 3 dB and going up by a factor of 10 times the wattage only adds 10 dB (a doubling of apparent sound pressure levels). So going from 7 wpc (8 dB of gain) to 40 wpc (16 dB of gain) should sound nearly twice as loud, but going from 40 wpc to 100 wpc (20 dB of gain) is roughly half again as loud). But we don't listen to specifications and the real world is harder to define than by simple numbers, that's why I say "commanding grip" and "improved resolution" (imaging and detail).
Yes, as Roger mentions, damping factor is my concern with the PrimaLuna as I tried a tube amp with my speakers years ago and got alot of bass flab.
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Just ordered PrimaLuna Dialogue Premium integrated from Upscale Audio. Stereophile class A rated, lots of tube related safeguards, auto-bias extends tube life), rolls EL34, KT88, KT120, etc., 32 - 43 wpc at 8 ohms, MSRP $3400. I have similarly rated speakers, so I'll let you know how it works out in a few weeks. PrimaLuna also sells power amp version that can be used in stereo or monoblock mode and a HP version with double the number of output tubes (from 4 to 8). Check out the reviews.
The old adage is that tube watts equal double the number of solid state watts. I'm an old fart and listen like one (to mostly small ensemble classical/jazz) but like a occasional Led Zeppelin sort of fix. Am a firm believer in amps maintaining a commanding grip on the speakers (lots of headroom) for improved resolution and driver safety. Have used 7 wpc, 40 wpc, and now 100 wpc solid state on these speakers. The 7 wpc did an amazingly respectable job but moving up to the 40 wpc turned the speakers from polite dinner guests into NFL linebackers in tuxedos. The 100 wpc hasn't added much.
Keep in mind that watts versus dB's is a logrthymic relationship, so doubling the power only adds 3 dB and going up by a factor of 10 times the wattage only adds 10 dB (a doubling of apparent sound pressure levels). So going from 7 wpc (8 dB of gain) to 40 wpc (16 dB of gain) should sound nearly twice as loud, but going from 40 wpc to 100 wpc (20 dB of gain) is roughly half again as loud). But we don't listen to specifications and the real world is harder to define than by simple numbers, that's why I say "commanding grip" and "improved resolution" (imaging and detail).
Yes, as Roger mentions, damping factor is my concern with the PrimaLuna as I tried a tube amp with my speakers years ago and got alot of bass flab.
Perhaps you should read the measurements section of the review given here. http://www.stereophile.com/content/primaluna-dialogue-premium-power-amplifier-measurements. From a very high (unusable) output impedance of 14 ohms the lowest that JA found was around 4 ohms which makes a miserable damping factor of 2 at best and 0.5 at worst (yes one can have damping less than 1). Looking at the graphs the amp has a lot of distortion and the transformers saturate at low frequencies. At one watt the bass distortion is 1% and although JA feels it is benign he doesn't mention the fact that there will also be large amounts of intermodulation distortion (IMD). Large IMD is no problem untill there is some bass. Its not that the bass gets a 2nd harmonic added, its that the nonlinearity produced by the bass causes all the rest of the music to be modulated by that bass wave. No bass, no problem, but then that's rather limiting isn't it. I think IMD needs much more attention and it is something I discuss in all my presentations.
Another way of looking at the damping problem is to view the response plots, figures 1 and 2. Given that most speakers are voiced with decent damping factors of 10 or more you will not be hearing your speaker as designed. Expect some pretty un-even response and no woofer control at all. The reviewer used 16 ohm Altec speakers. One should know that speakers of that vintage do not require high damping like modern speakers do. They were designed for low damping amplifiers of the 1950's and have fairly constant impedance curves and very good internal damping. Modern speakers rely much more on high damping amplifiers because that is what we have these days. The day that Edgar Villchur invented the closed box speaker changed the world of amplification and what amplifiers needed to do. Although I have great respect for Stereophile I find it odd that a component would get class A status from a listening test on a speaker that is no longer available, that is no longer typical of current speakers that most of us wouldn't even want.
Remember class A rating is based largely on the impressions of the reviewer in his particular system and hardly or not at all on measurements.
Here is a clever reader's reply at the end of the review online. Correct me if I am wrong; but shouldn't this be called PrimaChina?
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:D. Well, I see a few real important things here. Lets look at the speakers,and type of music played and
how loud, preamp compatibility, ,,, can one hit on all aspects with a tube amp ? :D
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I can make you a pair of monos or a stereo. I've been working with that tube since I was 16 year old. I made a AM radio transmitter with a 5 mile range with one. Send me a message if you want one.
PMs sent (one with an appology for not realizing your history).
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:D. Rodger,, if we can have a friendly audio-nut talk on the ph ,, I would very much enjoy..
Pat Paradis. :D
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Perhaps you should read the measurements section of the review given here. http://www.stereophile.com/content/primaluna-dialogue-premium-power-amplifier-measurements. From a very high (unusable) output impedance of 14 ohms the lowest that JA found was around 4 ohms which makes a miserable damping factor of 2 at best and 0.5 at worst (yes one can have damping less than 1). Looking at the graphs the amp has a lot of distortion and the transformers saturate at low frequencies. At one watt the bass distortion is 1% and although JA feels it is benign he doesn't mention the fact that there will also be large amounts of intermodulation distortion (IMD). Large IMD is no problem untill there is some bass. Its not that the bass gets a 2nd harmonic added, its that the nonlinearity produced by the bass causes all the rest of the music to be modulated by that bass wave. No bass, no problem, but then that's rather limiting isn't it. I think IMD needs much more attention and it is something I discuss in all my presentations.
Another way of looking at the damping problem is to view the response plots, figures 1 and 2. Given that most speakers are voiced with decent damping factors of 10 or more you will not be hearing your speaker as designed. Expect some pretty un-even response and no woofer control at all. The reviewer used 16 ohm Altec speakers. One should know that speakers of that vintage do not require high damping like modern speakers do. They were designed for low damping amplifiers of the 1950's and have fairly constant impedance curves and very good internal damping. Modern speakers rely much more on high damping amplifiers because that is what we have these days. The day that Edgar Villchur invented the closed box speaker changed the world of amplification and what amplifiers needed to do. Although I have great respect for Stereophile I find it odd that a component would get class A status from a listening test on a speaker that is no longer available, that is no longer typical of current speakers that most of us wouldn't even want.
Remember class A rating is based largely on the impressions of the reviewer in his particular system and hardly or not at all on measurements.
Here is a clever reader's reply at the end of the review online. Correct me if I am wrong; but shouldn't this be called PrimaChina?
Excellent points Roger. I have seen few, very few tube designers taking a stab at lowering IMD. It's a very real problem. The few that I know of working on the problem include yourself and Jack Elliano.
Best,
Anand.
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Excellent points Roger. I have seen few, very few tube designers taking a stab at lowering IMD. It's a very real problem. The few that I know of working on the problem include yourself and Jack Elliano.
Best,
Anand.
Terms such as Transient Intermodulation Distortion (TID) and Intermodulation Distortion (IMD) get referenced a lot. Here are definitions of the two items. TID is a major reason many solid state amps often don't sound so hot compared to a well designed tube unit.
TID Definition:
Transient intermodulation distortion, or TID/TIM, occurs in amplifiers that employ negative feedback when signal delays make the amplifier incapable of correcting distortion when exposed to fast, transient signals.
IMD Definition:
Intermodulation Distortion, or IMD is an amplifier or pre-amplifier (http://stereos.about.com/od/introductiontostereos/a/Components.htm) specification that measures non-harmonic frequencies added to the signal. IM distortion is the result of two or more signals mixing together that are not harmonic frequencies. These signals mix to create additional non-harmonic frequencies that are undesirable. Using the same middle C note example from above, if an amplifier creates a non-harmonic frequency of 300Hz along with the fundamental frequency of 440Hz, a third frequency of 740Hz will be reproduced (440 + 300), and 740Hz is not a harmonic of 440Hz. Thus, it is termed intermodulation distortion because it is between harmonic frequencies.
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:D. Amp builders terminology .. I gotta admit I would like to try a 200.. :D
But,,,, always a dam butt ! Ha. Will it mate with the pre ? How do you
even begin to know ? :D
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:D . Amp builders terminology .. I gotta admit I would like to try a 200.. :D
But,,,, always a dam butt ! Ha. Will it mate with the pre ? How do you
even begin to know ? :D
Not that difficult. The preamp out to power amp input impedance needs to be at least 10 to 1 ratio. In other words, the input impedance for the power amp needs to be at least ten times higher than the output impedance of the preamp. Some audiophiles like it closer to 20 to 1 to get a flat frequency response. The other item to look at is power amp gain vs. preamp gain. Most systems actually have too much gain between the preamp and power amp.
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:D. Well thanks .. I guess I'm on a #'s search about now. Sounds easy .. Ha
So pre-amp-speaker must all be within borders of each other to transmit properly ..
:D
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:D. Amp builders terminology .. I gotta admit I would like to try a 200.. :D
But,,,, always a dam butt ! Ha. Will it mate with the pre ? How do you
even begin to know ? :D
Will it mate? Yes, in most cases all preamps and poweramps are compatible much more so than poweramps and speakers. What is your specific concern?
As to the 10 to 1 ratio of impedance, I disagree that it is necessary or even helpful. Most systems will work fine with 2 or 3 to 1 as long as sufficient current and voltage are available. I think 20 to 1 is hard to obtain and pointless. But once audiophiles hear there is a ratio there is not stopping till one gets to infinity. BTW if anyone wants to try infinity here's how. In most tube amplifiers the grid return resistor to ground is the only load. It is typically 100K ohms but in many cases it could be 1 Meg ohm. If your preamps has some resistor on the output and they all do, you can take out the grid return resistor in the power amp and have infinite input impedance. However you can't do that with a transistor amp.
I do agree that most systems have too much gain and we make an attenuator that goes between the pre and power amp on the power amp end of the interconnect to reduce excessive gain and the noise that is usually present. The attenuator can also help unload the preamp if that is a concern. Most preamps can drive a 10K load and most poweramps are above that.
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Thanks for your response. You really should try a lower power tube amp if you care about reproducing the excellent midrange (which no one has talked about) that you speaker is known to have.
Other than myself and Nelson Pass not many designers come out and tell you what has to be done in designing a high power amplifier. If one is designing for 10-20 watts it is easy to bias the amp in class A whether it be tube or SS. It is not easy or economical to make a 100 watt or larger class A amp. Excessive headroom is a misconception unless you are talking about single ended tube amps, and even then it's not the issue....
The downside of power headroom is that most large amps don't sound so great at one watt because of what the designer had to do to make a high power amp. Thanks to Nelson for naming his work "First Watt". So much of the detail of music is in that first watt. When one gets a really clean system going I find that listeners actually turn the volume down because now they hear all the music without having to turn it up. There are speakers out there with very low sensitivity that need big amps, but your speaker is not one of them.
Roger- Very interesting discussion going on here in regards to high-powered vs low-powered amps and damping factor/current limitations. Makes me wonder what sort of implementations you used on your higher-powered amps (such as the RM-200II) to give it proper damping and to keep it from being current-limited as you say many other higher-powered amps are.
Is there a way for you to give some figures on the amount of damping and available current in your low-power vs high-power designs (RM10 vs RM200)?
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The RM-200 is unique in that it automatically and effortlessly goes from class A to AB1 to AB2. That means the driver is able to take the grids into the positive region for extra current by being direct coupled to the output tubes. Most tube amps have just the current and voltage available for the stated load and do not drive the grids positive. For 100 watts that means 40 volts peak and 5 amps. The RM-200 delivers a few extra amps as needed when the speaker impedance drops below the rated load of the tap. Most amps deliver less power as the load drops and that overheats the tubes. The worst thing you can do to most tube amps is load them below the tap impedance. The best thing you can do I call "light loading" which is to go in the other direction using a tap of lower impedance than the speaker. That is why the RM-200 has 4 impedance taps at 8.4,2,1 ohm. It also was one of the first amps to achieve 100 watts with one pair of output tubes without stressing the tubes.
The RM-10 on the other hand does not have an AB2 region as the output tubes are capacitor coupled as most amps are. However it does produce twice the power of typical EL-84 amps by virtue of a very high plate voltage and low screen. It is the only EL-84 amp that does that.
All my amps have a damping factor around 10 as less would cause a lot of speaker interaction, more wouldn't help much and would make the amp unstable. Most amplifiers I have measured with higher damping can be made to mis-behave on difficult loads.
I am only interested in designing new circuits and applications that have not been done before. There are plenty of companies who are building the same old stuff as everyone else.
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:D. There is an old RM-9 on the gon for 2 grand. Would this be worth
pursuing ? :D
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:D. There is an old RM-9 on the gon for 2 grand. Would this be worth
pursuing ? :D
Definitely not! Too expensive!
Six months ago I sold my RM9 mk2 for $1500. I got a good price when I bought it, so I passed it along. I typically see mk2 versions in the 1700 to 2000 range, used. On occasion a "distress" sale will appear for a coupla hundred less.
$2k is way too much for a mk1. :nono:
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:D. There is an old RM-9 on the gon for 2 grand. Would this be worth
pursuing ? :D
More recently, I had been watching used RM-9 MkII's for a little while as well. And to be honest with you, I think some of them were going for that price and more. I came across 2 a few months ago that looked interesting- one sold for $2000 and the other (which was in impeccable shape) sold for $2400 + shipping! I wasn't willing to pay that price, but I know this to be true as I contacted the seller afterwards and talked to him for a while. I dont think that he would have a reason to lie about. I've seen MkI's for sale for around $1600 - 1900, but not sure what the actual selling prices were.
I'm no longer looking for one as I found a newer RM200II-T instead which was a little more in line with what I was looking for.
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Used asking prices do vary widely, and some listings are pricey, but I stand by my previous comment. If you are patient you can get a mk2 in the 1700 to 2000 range.
Here are three recent examples:
http://app.audiogon.com/listings/tube-music-reference-rm9-mkll-2013-08-07-amplifiers-93601
http://app.audiogon.com/listings/tube-music-reference-rm9-mk-2-more-please-read-text-2013-11-22-amplifiers-14304
http://app.audiogon.com/listings/tube-music-reference-rm9-mkii-w-new-set-of-eh-el34-tubes-2012-12-09-amplifiers-55912
Keep in mind these are asking prices. Actual txn price could well be less.
On top of this, in past 18 mos I bought and sold my mk2 for $1500. So add these two transactions to the list.
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Used asking prices do vary widely, and some listings are pricey, but I stand by my previous comment.
No argument there. There are many factors to take into account for used equipment. Especially used equipment such as the RM-9, since many of them tend to be a bit older. Besides age and overall condition, you have the number of owners, possible modifications, hours of use on the tubes (perhaps additional sets of tubes). My point to the OP is that the used model he is looking at may not be as far off from the norm as you were leading on. Even some of your own examples are right there in the same range.
BTW, I have no affiliation with the owner of that current RM-9 for sale whatsoever.
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No argument there. There are many factors to take into account for used equipment. Especially used equipment such as the RM-9, since many of them tend to be a bit older. Besides age and overall condition, you have the number of owners, possible modifications, hours of use on the tubes (perhaps additional sets of tubes). My point to the OP is that the used model he is looking at may not be as far off from the norm as you were leading on. Even some of your own examples are right there in the same range.
BTW, I have no affiliation with the owner of that current RM-9 for sale whatsoever.
There's a bit of confusion here.
The RM9 amp on AG now that OP is inquiring about is a mk1. My point is that mk2's can often be had for the same price, even cheaper.
All my examples are for the mk2 version, VG condition, some with extra tube sets, all priced 1700 to 2000. Hence my conclusion that the current mk1 at almost 1900 is priced a bit high.
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There's a bit of confusion here.
The RM9 amp on AG now that OP is inquiring about is a mk1. My point is that mk2's can often be had for the same price, even cheaper.
Good point. I didnt catch that.
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Prices for RM-9s are going up from what we see. If we made that amplifier today it would sell for $9,000+. We made almost 1000 of them and they are still going strong with original caps that never seem to fail. Out of 3000 transformers we made here we have replaced only 3 some years ago and I have not replaced any in the last 15 years. The main concern it the condition of the PC board. Some are nice and green and some have browned out due to poor ventilation. Tube rollers have also loosened sockets on the PC board but we have a cure for that. We are now rebuilding and improving the driver by handwiring it on an aluminum plate so there is no more circuit board and the balance is now self adjusting. This runs $1500 but makes a great improvement and extends the life of the amp so far into the future I cannot say.
The RM-9 is so easy on tubes that we have seen tube sets go past 15,000 hours. That's 15-20 years for some owners. We have installed Cardas binding posts on many units when the come through for a tune up. For an amp that is almost 30 years old its pretty amazing. I can honestly say, other than the driver upgrade we are doing there is nothing else I would change given what I have learned about amplifiers in the past 30 years.
For those of you who want the best RM-9 ever made we do have a limited number of the SE edition. There are several owners of that amp on this forum, rbwalt being very active. The SE has a 3 tube driver which allows it to provide extra current for difficult loads. The SE is completely hand wired, has test points for every tube including the drivers. All tubes can be tested in place. Each output tube is separately fused with fuse indicators. Bias and output balance pots are top chassis mounted and easy to adjust.
All RM-9's are Ultralinear and allow the use of almost every power tube. We even have users with KT-120s who use just 4 output tubes as that is all you need with the larger tube to obtain the same power.
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Used asking prices do vary widely, and some listings are pricey, but I stand by my previous comment. If you are patient you can get a mk2 in the 1700 to 2000 range.
Here are three recent examples:
http://app.audiogon.com/listings/tube-music-reference-rm9-mkll-2013-08-07-amplifiers-93601
http://app.audiogon.com/listings/tube-music-reference-rm9-mk-2-more-please-read-text-2013-11-22-amplifiers-14304
http://app.audiogon.com/listings/tube-music-reference-rm9-mkii-w-new-set-of-eh-el34-tubes-2012-12-09-amplifiers-55912
Keep in mind these are asking prices. Actual txn price could well be less.
On top of this, in past 18 mos I bought and sold my mk2 for $1500. So add these two transactions to the list.
In looking at those listings I see they are rather old and prices change rapidly when something gets recognized. Look at what happened to the Marantz amps and they were lots more of them.
The last listing given was a great deal but it was in late 2012. Sorry we can't go back in time.
As to the range of prices, anyone who watches used gear on AG or eBay knows that something can go for a song sometimes and another time fetch twice the price. In my tape playback preamp project we are watching Studer machines of similar condition sell for $600-$3000, go figure. Revox A77s go for $100-$1000 and they made 350,000 of those. We made just 930 RM-9s and only 19 SE amps, one of which I am keeping.
Here are some recent comments on the RM-9. http://www.audiocircle.com/index.php?topic=124084.msg1307677#msg1307677
One comment to correct. The power is not lower with EL-34s. It is the same with all the power tubes because they are not pushed to their limits. I purposely did this and made the amplifier useful with all the popular output tubes so making this an amplifier that is useful in comparing output tubes. At the time, and even more now, people are commenting on the difference in sound in output tubes but they are often comparing those differences in different amps which is not the proper way to do such a comparison. The amp needs to be the same amp otherwise how does one know how much the different amps are causing the difference in sound. How many amps can we name that allow that.
For those of you who are new to this hobby the first review of the RM-9 by Dick Olsher brought strong objection from David Manley who insisted that amplifiers must be tube specific due to the nature of tubes. He gave many reasons, most of which were simply not true. This resulted in an open discussion in the manufacturers comments of Stereophile, something that rarely, if every has happened before. But the editor and the public must have liked the interchange and its often what people remember when I meet them at shows. These became known as the Manley-Modjeski letters. In them we were the first, I believe, to coin the term "tube rolling" and joke about cotton gloves (which are absolutely silly). There were five long letters, the last two being published simultaneously with a further letter from Kevin Hayes at VAC. If there is interest I will try to dig them up.
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Hey Pat
Not sure if you've seen this little review by GT Audio over in the Critics Circle. It's a review wrintten back in Feb, he had been suing a Bryston 4B and had the opportunity to use an RM9 MKII for a while. I thouht it was a good read
Thought it may interest you.
http://www.audiocircle.com/index.php?topic=124084.msg1307723#msg1307723
Also, besides the Audiogon u nits given fo prece ref, I beleive I've seen a couple RM9 MKII's sold here within the past year or so for < $2K.
Edit: Can only find the 1 MK recently sold here http://www.audiocircle.com/index.php?topic=118857.msg1249521#msg1249521
Sure there were a coupl emore.... :scratch:
-jay
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In looking at those listings I see they are rather old ......
rather old?? :scratch:
they date back to 7 mos, 10 mos and 18 mos. I guess the reader will determine what "old" is.
The RM9 does not pop up used very often, so that historical data is all one has to go on.
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:D. Would it be cool to scoop this 9 and send it for updates ? Seems logical ? :D
My old buddy Mike bought one ? Interesting ! He told me about the 38's ,,,, ha
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:D. Would it be cool to scoop this 9 and send it for updates ? Seems logical ? :D
My old buddy Mike bought one ? Interesting ! He told me about the 38's ,,,, ha
Do you refer to user Topround in NJ? I know him well. He bought my RM9 mk2. He sent it off somewhere for some massive mods / upgrades. Don't know the details, but you can check with him. I think he's very happy with the result.
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:D. Yes,, that's my old buddy .. Ha. He's good people.
One step ahead of me it seems ! Ha who the heck did his mods ? :D
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:D. Would it be cool to scoop this 9 and send it for updates ? Seems logical ? :D
My old buddy Mike bought one ? Interesting ! He told me about the 38's ,,,, ha
If you want it updated I suggest you send it here. I have had to re-do many non-factory updates. In the last one we had here someone substituted some rather small main filters in order to use "audiophile"grade caps. That certainly didn't help the sound of the amp.
What I mostly see in "up-grades" is blind part switching where the up-grader pays no attention to the function of the part often putting an expensive part where it does no good and missing a place where an expensive part might do some good. The most amusing upgrade I see is rectifiers. People have been convinced that there is something great about HEXFREDS or fast rectifiers. "Fast" is better than slow, right? What amuses me is when they bother to change all eight bias rectifiers who are conducting so little current that their speed is of no consequence. Of course anyone who shells out bucks for upgrades will be pleased with the results, he has to be for what he spent.
We only use "audiophile" parts on special request. Most of our up-grades are to add the power supply chokes and additional filters and Cardas binding posts to the MK-Is. There are no upgrades to the MK-II at this time. Perhaps I should invent some.
Many upgraders will admit that they are not circuit designers and do not understand circuits. Oddly they feel qualified to substitute parts in circuits they don't understand. Wouldn't you rather have someone who knows the circuit work on it?
One last recommendation. Stay away from "audiophile" caps made of exotic materials. It takes many years of experience, trial and some error to make reliable capacitors. I have seen too many silver and oil caps short out, burn up tubes and resistors. I wouldn't buy a cap from anyone but a large maker with years of experience. One other point for the technically minded. There is a lot of talk about dielectric absorption (DA) and materials. So here is the science. Dielectric absorption is only a factor if there is a changing voltage across a capacitor such as in a speaker crossover. In an amplifier there is no changing voltage across the capacitor. So what does DA matter? The capacitor sellers are surely not going to mention that little problem with their claims.
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Is there any sonic improvement with your hand wound transformers? Really worth the $1k expense?
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:D. Roger ,,,, for God sakes ,, STOP MAKING SENSE ! Mods are not worth it unless you
" hear " them and are " happy " with the outcome. So, the mod has to be benched
and voiced and tried and trued. So if I bought this amp , can I get the up-dates
done ? and the cost ? Or is it cheaper and smarter to buy new ! A 200 ? :D
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Is there any sonic improvement with your hand wound transformers? Really worth the $1k expense?
Currently we are winding everything here, I have given up on outside winders who can't seem to follow my instructions. Outside winders have a variation in high frequency cutoff as bad as 2 to 1. In house we can get that down to 20% and I can do better than 10%. Although I supervise the winding how can I take a new person and expect him to do what I have been practicing for over 30 years? Here's an important difference. Since I designed the transformer I know what variations make a difference and what do not. It's a little like baking, each cake turns out a little different but the differences are far less when the baker knows what is important and what is not. When winding each transformer there are often decisions that have to be made as it is happening. I have a "exemplar" output transformer with the highest frequency response I ever obtained and no one has been able to match or beat it... though some do come close.
Given the cost of most amplifiers today and that we are one of a very few companies that winds in house, I do think its a pretty good deal.
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:D. Roger ,,,, for God sakes ,, STOP MAKING SENSE ! Mods are not worth it unless you
" hear " them and are " happy " with the outcome. So, the mod has to be benched
and voiced and tried and trued. So if I bought this amp , can I get the up-dates
done ? and the cost ? Or is it cheaper and smarter to buy new ! A 200 ? :D
Of course you can get the mods which we customize to the owners wishes. Typically people are spending $500-$1400. I don't push upgrades because I think both the MK-I and II are fine amps as they stand when properly serviced.
The RM-200 is a different beast. I wanted to make something with half as many tubes and keep the price reasonable. As I said to keep making RM-9s was getting very expensive mainly because of the potted transformers (who does that these days or even then).
All I can say is that people like how my amps sound, they are reliable and we give good service to our customers. Yesterday a guy called me wanting an RM-10 but because he has very sensitive speakers (102 dB/watt) he switched to the OTL-1 which is a very clean 3.5 watts vs 35 for the RM-10. http://audioshark.org/music-reference-176/music-reference-rm-otl-1-a-5121.html#.U6MpCvldW3s
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Currently we are winding everything here, I have given up on outside winders who can't seem to follow my instructions. Outside winders have a variation in high frequency cutoff as bad as 2 to 1. In house we can get that down to 20% and I can do better than 10%. Although I supervise the winding how can I take a new person and expect him to do what I have been practicing for over 30 years? Here's an important difference. Since I designed the transformer I know what variations make a difference and what do not. It's a little like baking, each cake turns out a little different but the differences are far less when the baker knows what is important and what is not. When winding each transformer there are often decisions that have to be made as it is happening. I have a "exemplar" output transformer with the highest frequency response I ever obtained and no one has been able to match or beat it... though some do come close.
Given the cost of most amplifiers today and that we are one of a very few companies that winds in house, I do think its a pretty good deal.
OK, very cool. So does this mean that all amps have the $1k premium applied since you wind them yourself or?
So which price is paid?
[/size]RM-200 MK II 100 watt/channel Push-pull KT-88 [/font][/size][/font]$4,900
[/color]RM-200 MK II-T As above with transformers wound by Roger [/size][/size]$5,900[/font][/size][/font]
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:D Rodger,, you have 9SE's for sale or you were stateing you have sold some past ?
So if a guy sends his old 9 there, it's 15hun for you to modernize totally ,, even
Like you say unnesecarily ?? :D ( sonically not worth the $,but longevity wise,, well worth )
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:D. Well good Lord I've done it now.... The 9 on the Gon is gone my way. I have ten toes and
Fingers crossed its a good one. Anyone know a guy named Paul Hensel ? I'm very excited .
A lot of press on this amp.. All good too ! Talked to Roger today and was going to buy a 200
from him but the offer I put in on the 9 was accepted. Yikes .. We will talk again Roger.
About this amp and just what to do ? The 200 is 3* the cost so I saved some $ and still get to
sample you workings. :D Can't wait ,, I really can't .. :D Happy Monkey here !
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Congrats !! Hope you really enjoy it, anxous to hear what you think.
You are having it shipped up here to Canada I'm asuming ? You don't figure it is worth having the guy ship it direct to Roger for a check up and tune up ? Would sure save you some serious shipping ocsts and cross border hassles if you end up deciding to ship back to Roger later
-jay
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:D. I will see what Roger thinks. The owner says he had Bill Thalman from CJ check it out .
Clean bill. And he said this was a low hour second system amp. Hummmm ? :D
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Bill T is Top Shelf, great designer of valves, upgrades, as well as troubleshooting and repairs.
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:D. Thanks 007 , so he is of this world. Thanks very much. He wouldn't know the amp like Roger of
course,, but good to know. :D Can't wait to hear the sound of those sweet-sweet valves
playing in perfect harmony. As much as I would like to get this to Canada ASAP,,,, I really should send it in on a Pit Stop. Let the Maker eye-ball it and stamp it green. Dam,, 8)
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The RM 9 I owned sounded great with the Infinity RS 1s driving the Emit/Emims, along with a c-j Premier 3 and SOTA Star/SME V/Koetsu Rosewood, I wish I had that system back! You should have a big grin after plugging the amp in your system.
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Bill T is Top Shelf, great designer of valves, upgrades, as well as troubleshooting and repairs.
+1 for Bill Thalman. Have always had a good experience dealing with Bill.
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:D. Thanks and good to know 007 . I really can't wait. This is vintage gear. Like a vintage sports car. You can look and you can hear.. Hear the difference. :D