Whats up at Aspen?

whubbard · « **on:** 11 Apr 2009, 05:35 am »

So Hugh,
How are things going?
Seems to be fairly quiet around here. Last I remember you were working on the GK-1 MK2, how is that going?
Hope all is well

-West

AKSA · « **Reply #1 on:** 11 Apr 2009, 07:42 am »

Hi West,

Thanks for the post - things are fine, I'm working on the Hawk (aka GK2), that's true, and it's all but done.

Now I'm watching the world with grave and building interest, particularly the fortunes of GM, and I've recently spent a couple of days helping a local enthusiast fix his Silicon Chip amplifier. I'm also putting the finishing touches to a new amp, a 150W//8R version I'm calling the Maya.

I have quite a fascination for pre-Columbian American history!

How are things in the Big Apple, West? How is your rig sounding now? Do tell us all about the destination, now that the journey is over!

Cheers,

Hugh

whubbard · « **Reply #2 on:** 11 Apr 2009, 04:54 pm »

Hugh,
Glad to hear all is well. I betting the Hawk will sound wonderful. Is it still going to use 2x 6922?

Quote from: AKSA on 11 Apr 2009, 07:42 am

How are things in the Big Apple, West? How is your rig sounding now? Do tell us all about the destination, now that the journey is over!

Well the American market is recovering, which is good; however, I'm thinking we'll see one more big dip before this is all over.

The rig is sounding nearly perfect. I want to spend a bit more time working on internal wiring, as there is still intermittent hum. It soft, and doesn't always occur, but I'm striving for perfection here. Once all that is settled, I've got to finally box my Peter Daniel DAC, and put it into my system. It's just been sitting on my workbench fully built for over half a year and I haven't even heard it! After all this, I will finally call my DIY project 'finished'.

Obviously, as you know, that doesn't mean it's ever really over. This summer I will be building that turntable, which I'll need a Paris for (need to send you an email on that in the near future). Then after the that, maybe a few room treatments. This hobby is never really finished. Luckily I have a system that I can enjoy right now, and that I've very happy and satisfied with. I'll always be looking forward, but I also want to make sure I have something to enjoy in the present.

-West

Jens · « **Reply #3 on:** 14 Apr 2009, 09:04 am »

Quote from: AKSA on 11 Apr 2009, 07:42 am

I'm also putting the finishing touches to a new amp, a 150W//8R version I'm calling the Maya. I have quite a fascination for pre-Columbian American history!

Hi Hugh,

Interesting news!

About the Maya, I would like to draw your attention to the fact that Rega has a power amp called the Maia. The spelling is slightly different, though ... and I don't expect anyone would confuse the two.

Looking forward to hearing more about the Hawk

AKSA · « **Reply #4 on:** 14 Apr 2009, 12:08 pm »

Hi West,

The Hawk uses a 6BL8, which is a triode/pentode. The pentode is used in cathode follower mode, while the triode is used to drive the screen grid. These tubes are plentiful, used in most TV sets from the fifties to the seventies, and there is a wide NOS choice available.

The new preamp will be sold fully built, while the GK1 continues as a kit. The Hawk is a completely different topology though it does use a high voltage SS stage for voltage amplification. Results: Top end little changed, bass enhanced, midrange, particularly vocals, euphonic and musical. Image is both deepened and widened, and engagement is, well, you know the rest....

Jens,

I will stick with the name Maya, but call it the Maya CB280, indicating the power into 4R and the contribution of Colin Brown, in Vancouver, who has helped me more than I ever expected. Rails are 56V, it's a very, very lovely amp, with all three stages unique. I've done a number on the output stage, which uses a unique driver topology to clean up the crossover event rather like a Class A, but with Class AB efficiency. I have managed to get it all into the same size case as the Soraya, and I think this will be quite a hit, in fact.

Thanks for the interest!

Cheers,

Hugh

Jens · « **Reply #5 on:** 15 Apr 2009, 08:45 am »

Hi Hugh,

The Maya sounds very interesting topology indeed. Will it be the Soraya's little sister or big sister

- sound and pricewise?

bluesky · « **Reply #6 on:** 15 Apr 2009, 12:28 pm »

Hi Hugh

I could never quite understand the stance taken on tube rectification other than some insisting that it sounds better, but it always seemed like swings and roundabouts to me with solid state appearing a much more practical solution but I must stress I am no expert on these matters.

I applaud your use of the tubes though, so often good tubes are given short shrift for no other reason than not being popular, although marketing can a be such a fine line at times (some damn fine motorcycles have sunk without trace due to this factor). However in this case, there are sufficient NOS brands for customers to roll to their heart's content which provides that essential man/machine/art interface that is so much a part of audio and music.

Cheers

Ian

Jens · « **Reply #7 on:** 1 May 2009, 01:09 pm »

Hi Hugh,

Could you give us a pointer as to how the Maya would be ranked in relation to the other Aspen amps - or is it too early yet?

Quote from: Jens on 15 Apr 2009, 08:45 am

Hi Hugh,

The Maya sounds very interesting topology indeed. Will it be the Soraya's little sister or big sister - sound and pricewise?

whubbard · « **Reply #8 on:** 1 May 2009, 02:25 pm »

I'd bet better or very similar to the Soraya.
Yet worse than the Glass Harmony.

Just my guess...

-West

AKSA · « **Reply #9 on:** 1 May 2009, 11:33 pm »

Hi Jens and West!

Not yet, bit too early, still finalising the front end dimensioning, even though the boards are all done and ready to roll. We need to choose feedback levels (and hence damping factor) very carefully, and this is where we are fiddling about. We (Colin and I) are searching for a slightly more tubey sound - by which I mean something which really tugs at the heartstrings. Yes, it can be done in the design of an amp, it's quite extraordinary. I've recently been using simulation with LTSpice, somewhat inexpertly, but studying the Fourier analysis to give the distortion profile in detail, by precise harmonic. This seems to be bearing fruit and slowly we are building up a repertoire of simulation v. listening tests. It is this correlation which lies at the core of enlightened design, sadly not much of it is done.

The Maya will be for a different market, though, 150W into 8R, 280R into 4R. Soraya is 108W, 205W.

After developing a number of amps over the years, I'm convinced, knowing people's tastes now as I do, that better or worse is inappropriate, though one is sorely tempted to use these words. Different seems appropriate. And some will like that, and some will dislike it, this is such a subjective area. Heck, it borders upon the religious for many. But it's fascinating, no question about that!

One man's meat is another man's poison? Does that fit?

Ian,

As a general rule in this mad, mad world product success is determined by marketing, not by product quality. Good example was Windows 95, $500 million spent on the marketing, a great success! The best car I ever saw from the 1920s was the Hispano-Suiza, an absolute masterpiece, but Rolls Royce had the jump on the marketing, even though in many ways the technology of Rolls Royce was way behind. Same could be said of Bugatti. People raved about the TRX850 Yamaha, a Japanese Ducati, they'd say, yet few were sold, same with the ZRX1200, which I own and which I consider the best all rounder in the large displacement market, even today.

Conversely, the worse the marketing, within reason, the better the product, largely because the money was spent on R&D. I like to think I'm in this category!!

Hugh

VYnuhl.Addict · « **Reply #10 on:** 5 May 2009, 08:39 pm »

Greetings!,

Well said Hugh!, the topology design aspect always seems by far the easiest aspect of a new design, functionality and bringing it to quality sonics and operation ranks 2nd. The hardest part is the length of time after this part is complete to bring out the best of the design with the careful implementation of compensation, parts choice and the time it takes to fiddle with operating points over the time after a final design has been approved. Lots of listening in Canada, more recently alot of simulations in Australia ,and help through sometimes frustrating times in the design process

, a very give and take process overall. I think Hugh nailed the ideology the first time around with the Aksa, aiming for that Tube Esque sound except naturally there are compromises in each. With the Maya the goal from day one was not neccesarily to sound like a tube amp but to convey the natural flow, ease of dynamics and presentation, without sounding Solid State but retaining the potential realism and accuracy of a great SS design.. I feel this has been accomplished in spades, its definately different from the Soraya and Lifeforce. Its very hard to scream that one amplifier is better than the other because its always such a fine and delicate balance between many variables that portray the final Sonic end product. But!, needless to say Im very happy with it and currently enjoy music for hours on end in effortless dynamics, imaging and unfatiguing long term sonics, a very refined ,smooth performer

.

Best Wishes
Colin

gaetan8888 · « **Reply #11 on:** 6 May 2009, 05:15 pm »

Hello Hugh and Colin

For the simulation with LTSpice did you use the transistors models from LTSpice or better models ?

About the Fourier analysis and the distortions profile, I remember that Jean Hiraga, many years ago, say that the best sounding amps did have mostly even harmonics distortion and going lower level at higher frequencies, like a nice triangle shape, and there was no high frequencies distortions harmonics.

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High frequencies distortions harmonics would just kill the musicality and soundstage.

Bye

Gaetan

AKSA · « **Reply #12 on:** 6 May 2009, 11:25 pm »

Gaetan,

I think there is a very good likelihood Jean Hiraga is correct.

Incidentally, he is a personal friend of one of my customers in Geneva and has even heard the AKSA 55N+!!

Cheers,

Hugh

gaetan8888 · « **Reply #13 on:** 7 May 2009, 07:56 pm »

Hello

Jean Hiraga was one of the first guy who say that those .0001 % distortions numbers did mean nothing and that the frequencies and the type and the distribution of the frequencies of the distortions harmonics spectrum was more important. Arround 30 years ago, in the magazine La Revue du Son, he wrote a very good article showing good sounding amps distortions spectrum, etc.., like the drawing I done. I was reading all of his articles.

30 years ago, that Hiraga's article made a big change in my way of thinking about power amps distortions.

Bye

Gaetan

AUDFILE74 · « **Reply #14 on:** 9 May 2009, 06:22 am »

hi hugh, if you don't factor in power increase and just look at performance,sonically how does the maya conpmae to the soraya? what was the design goal for the maya?

bluesky · « **Reply #15 on:** 9 May 2009, 07:07 am »

Hi Hugh

Just been reading a book which kept referring to that Hispano-Suiza, which I know little about, which means I must find out more.

I recently tried to work out what I could sell to fund a small second hand super motard type of bike to go riding again. Well, that and a Teenage Mutant Ninja Turtle type of Dainese back protection outfit. I can't believe it, my kids are standing firm and telling me off about the idea, ranting and raving, pointing fingers, waving arms, the whole bit.

Crikey, I thought parents were supposed to do that!! Well, it seemed like a good idea at the time!

Ian

AUDFILE74 · « **Reply #16 on:** 14 May 2009, 12:16 am »

so when will the maya be available?

AKSA · « **Reply #17 on:** 14 May 2009, 02:20 am »

Steve,

I'm gunning for two more months. I have much to do, I can't believe every time I do this what is involved.

As for sound quality, I can't yet give you a definitive answer, I'm still putting mine into a suitable case. BUT, maybe Colin can tell you, he has one up and running and says it's quite extraordinary.

Design goal was to achieve even more transparency whilst maintaining resolution, low distortion, and ability to run with difficult reactive loads like Electrostatic speakers. In the process I learned a bit about simulation software, and designed a very good board, and built it out a bit for more power. The refining of the circuit values has been Colin's baby, and this has taken time as many factors are finely balanced.

I'm sorry for the delays, but they would not be delays had not the word slipped out, I should be more circumspect!

Hugh

JohnR · « **Reply #18 on:** 14 May 2009, 03:12 am »

Quote from: AKSA on 1 May 2009, 11:33 pm

People raved about the TRX850 Yamaha, a Japanese Ducati, they'd say, yet few were sold

Well, it was ugly and awkward looking, a transparent imitator, and cost almost as much as the real thing...

AUDFILE74 · « **Reply #19 on:** 14 May 2009, 03:48 am »

THANKS FOR THE INFO HUGH! i'll have to find colin on here and get his take then