[kyrill]

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

[DSK]

...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 ... 

[andyr]

If you can double the power of the Soraya without losing any of the purity, delicacy and refinement, then ... 

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? 

Regards,

Andy

[DSK]

If you can double the power of the Soraya without losing any of the purity, delicacy and refinement, then ... 

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? 

Regards,

Andy

I didn't really need the worked V8 I had 20 years ago either ... but I still miss it. 

True, my speakers are an easy load though only 83db or so .... but if I could have double the power without giving anything up ...

[Jens]

Hugh, this thread is filled with goodies - great input input from knowledgeable and enthusiastic Aksaphiles 

Perhaps it would be worth making it a "sticky"?

[Rom]

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

[AKSA]

Folks,

Done, topic merged and subject amended.......  thanks Jens, great idea 

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
 

[markus46]

...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

[jules]

 , 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

[AKSA]

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

[jules]

Thanks Hugh ...

 , 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 

jules

[VYnuhl.Addict]

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
   

[kyrill]

thx for the explano, no c4 mod for me

[AKSA]

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

[stvnharr]

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

[andyr]

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

[AKSA]

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

[stvnharr]

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

[RonR]

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.

[andyr]

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?? 

Regards,

Andy