Building the ultimate DIY power amp

[Dave S]

It's been done:

http://www.beardmorebros.co.uk/

Check out "John's new project" for a Morris Minor that beat all the Ferrari's on it's first race outing!!!

Back to hifi: Maybe Linn is not in the same league as Krell, Levinson etc, but I am much happier with my home made hifi system than I was with an expensive Linn active system.

I have seen the schematic for a KSA100 posted on this forum some time in the past - it's not rocket science. However I suspect that getting a clone to sound the same (if that's what you want!) would be very difficult - because as most on this site know, everythng makes a difference to the sound (unless you're Doug Self).

[Damon Hill]

The British are VERY into DIY; this has got to be
the ultimate:

http://www.a1steam.com/

I'm challenged enough just coming up with chassis
and heatsink designs.

[AKSA]

Mikeks,

With sad resignation, for I too think as you do, I have come to the very same conclusion.

I've tried cascodes, Lender configurations, Rush cascodes, CFP VASs and diff pairs, complementary VASs, multiple CCS creations including current mirrors and folded cascodes, I've tried the lot and spent hundreds of thousands of dollars chasing the holy silicon grail.

The outcome was no different to any other technology; all roads lead to the simple, well engineered approach which happens to be the most widely used; the single-ended VAS transistor. This is, in fact, technological convergence; this approach is so widely used because it gives the best results, rather like liquid-cooled, front engine, rear drive on automobiles.

Cheers,

Hugh

[millwood]

Originally posted by tcpip
But my question is not about any amp he has designed, but rather about what he --- or someone like him --- can design. With a garage full of $10K of equipment, and all his knowledge and experience and passion and patience, can someone in his position beat the big brand amps if he didn't have kit builder constraints?

the answer is absolutely yes. and even if you replace the name AKSA for anybody, here or not, the answer is still yes: anyone can design an amp that better any amp from a big name manufacturer, including krell, pass or hugh. there is no doubt about that.

however, there are two problems with that assertion:

1) you are talking about a hypothetical event, a possibility. I can win a lottory, I can be another Bill Gates, I can design a car that bests a Ferrari. I can ....... But I am not. and Hugh isn't designing an amp without contraints. so what real good does it serve to discuss something that isn't true?

2) we don't listen to designs. We listen to a physical, tangible amp. and there is a lot of "art and science" in turning a design into an actual thing, either on a one-off basis or in mass / quantity production. That is where a manufacturer has a hugh advantage over us.

Originally posted by mikeks
After a great deal of research, i have no choice but to accept that the simple generic gain-stage topology as used by Self, AKSA....Rod Elliot...etc...simply cannot be improved upon by so-called 'symmetric'...quasi-symmetric designs, 'current' feedback...etc....period.....

rather disappointing....as i had hoped that the visually appealing 'new-age' designs would come up trumps.....

I would agree with that. I found out also that usually the simplest linn amp sounds the best, to my ears. and I cannot detect sonic improvements that supposedly exists in those more complicated designs. so for me the simpler designs excel.

[destroyer X]

I strongly believe your ideas, for me, no doubts, Hugh Dean, this is the man, and AKSA may be the amplifier.

I am waiting, i will see and hear them... i will tell you a lot.

If bad i will open my damn mouth loud and clear before banishment!

300 hundred box is not a joke for me!

Carlos

[JonMarsh]

This is, in fact, technological convergence; this approach is so widely used because it gives the best results, rather like liquid-cooled, front engine, rear drive on automobiles.

So, then what are the NSX and Porshe lovers to do in a world like this?

I suspect they'll still drive what they like...


~Jon

[grataku]

Originally posted by AKSA

I've (tried the lot and) spent hundreds of thousands of dollars chasing the holy silicon grail.
Hugh

'Hundreds' of thousands of dollars_

Aussie dollars or real dollars?
This is the kind of stuff that drives me nuts!
I like you and admire your small success story in the audio business. Considering the crap I see floating around out there. I think you sell a great little amp kit that plays good music at a very honest price.
I had a very long post written about this but I just watched the last lord of the ring movie so in the spirit of diy fellowship I just erased everything and decided to drop it.
Please don't let me catch you again telling these baa_aa_ls, ok?

[Peter Daniel]

The ultimate is always changing, both in commercial offerings, and in whatever a diy-er can put together. I have no doubts that an individual, when motivated enough, can build better stuff than established high-end manufacturer, if not only for the fact that when building one off unit, certain approaches can be still justfiable, which might not be the case in a commercial production run, where overall costs are much bigger issue.

I still don't think that whatever Madrigal builds, can be regarded as a holy grail of amplification. While their designs are very good from technical POV, they can be much further improved when certain mods are performed. I'm still not sure why they don't do that in house, in a first place.

I'm currently modifying ML38S preamp, so I'm talking from personal experience.

[millwood]

Originally posted by JonMarsh



So, then what are the NSX and Porshe lovers to do in a world like this?

I suspect they'll still drive what they like...


~Jon

that might be a different question: more like Ferrari vs. Acura / Honda vs. Porsche. (or a Pass vs. krell vs. mcintosh comparison). there is no DIY element here.

the better analogy here is Ferrari vs. a modified Civic vs. a modified 427 kit, etc. The DIY is clearly present in the last two cases.

You can clearly get a Civic to a Ferrari level in terms of performance. but it would be hard to persuade any Ferrari owners to give up their vehicles for that Civic,

Again, if you just care about sonic performance, you can clearly DIY an amp that's better than a Pass or krell or whatever you want. But you will miss out on others.

[tcpip]

Originally posted by Terry Demol
I think you missed a simple most important
factor that differentiates Self from Pass & Dean.
Self doesn't do careful listening tests as part of his
development methodology, they do.

I was thinking about this myself.
This difference, in my opinion, may differentiate the degree of success an individual designer has. This is a difference in the set of approaches a designer attempts. Some designers will try to build Class A and compare with Class B --- others may not even attempt Class A, saying that modern Class B amps distort too little already. This way, the second class of designers may miss out something interesting that Class A can provide.

Some designers may try changing components or layouts specifically for A-to-B comparisons, while others may say that layouts are critical only in the RF range, hence there's no need to try this approach. And the second class of designers may miss out some gems which are layout-dependent.

I put your example of listening versus non-listening in the same category. There are some things you have try out before you discard them. Listening for sonic differences versus gauging quality purely based on measurements is one of those things to try. Some designers try them, others don't.

But basically, this means that there's nothing stopping a good, competent and committed individual who does try out all these things from beating the Krells and MLs?