New Naksa Amplifier! Quick Initial Impression......

Brad · « **Reply #60 on:** 6 Jul 2010, 06:29 pm »

Hugh,

That's the same picture you sent me of mine about to be dispatched

AKSA · « **Reply #61 on:** 6 Jul 2010, 11:10 pm »

Ah, Brad Hawkeye!

It's actually a mixture. I took several pictures, one with John's board on it, as he wanted one without the heatsink to reduce shipping, and then I removed it, took your module, attached it to the same heatsink, then took a few more pictures for a better angle. It might inded be John's, but then, it could be yours too, I forget. The boards are nevertheless identical, which is the wonderful thing about pcbs, all the same, easier to build, less mistakes.

Gee, I gotta be real careful around here......

Hugh

Aussieamps · « **Reply #62 on:** 6 Jul 2010, 11:34 pm »

Hi Hugh

Well done mate!

They look awesome.... I hope you sell a ton of them!

Cheers

Anthony

AKSA · « **Reply #63 on:** 6 Jul 2010, 11:36 pm »

Thanks, Anthony,

Nice of you! Let's see, a tonne, that's 645 sales comin' right up, I look forward to that......

And I hope you sell lots of yours too, fine amps and magnificent boards, even better than mine, there, I admit it!

Cheers,

Hugh

AKSA · « **Reply #64 on:** 6 Jul 2010, 11:45 pm »

PainKiller (Ola?),

My apologies, didn't answer your post - answer is YES, $AUD850 plus shipping and 4% paypal surcharge.

That's indeed the price of the NAKSA, and a worthy successor to both the AKSA and the Lifeforce, I'm very, very pleased with it. It is highly musical and has wonderful imaging and bass.

I kinda half apologise for developing these things quickly, but then, the customer is a ruthless mistress, and demands new designs every few months lest she lose interest...... ah, the capricious marketplace. However, in my defence, I am a serial amp developer, can't stop, it's a part of my identity, and personally I feel there is a long way to go to true high end audio.

This design is essentially a single ended push pull amp, that is, it has the essential distortion profile of a single ended amplifier, albeit with global feedback (only 31dB of it), whilst sporting the output topology of push pull for its efficiency. I have found that the single ended topologies create a very favorable, musical distortion spectrum, and this amp certainly bears it out with a stellar sonic presentation I hope will soon become evident from recent buyers, who started with Hegemony, aka Russell, and are building fast.

Cheers,

Hugh

Seano · « **Reply #65 on:** 7 Jul 2010, 02:28 am »

Am I the only person thinking about a pair of active, bi-amped NAKSA V-Sonics?

Or is it just that I'm suffering from a simple case of ambition & ignorance in the face of financial inadequacy?

AKSA · « **Reply #66 on:** 7 Jul 2010, 05:31 am »

Seano,

I live in the quiet, understated hope that indeed you are not the only one......

As for being financially inadequate, consider the life of an audio designer, my friend.

Cheers,

Hugh

jkeny · « **Reply #67 on:** 7 Jul 2010, 07:20 am »

Hugh, let's hope all that changes with this new amplifier creation from your furrowed brow. The more I read of your design concept & execution the more I believe this will be a run-away success.

Of course you need to girder your loins for the onslaught of objectivists - what is that great term you use? - not credentialism but similar?

AKSA · « **Reply #68 on:** 7 Jul 2010, 07:49 am »

John,

Another off today, to Ken Li in LA, here's hoping it's quick transit and performs as it should! Two yesterday, yours one of them, this is promising, but I need a few reviews to back up Hegemony's - he is coming over for coffee tomorrow and full update to V2.0, which is the current production version.

Actually, I'm extremely lucky, as I love this game, the work is a pleasure, and when you have something people are happy to buy it's very, very stimulating and satisfying. I have now fully polished the instructions, but I need to get some more printing supplies, paper, and it would be lovely to have the front page printed in colour to exploit that marvellous recent photograph I took of the NAKSA at a jaunty angle.

The design is proving ideal for production; in the last three days I've brought four to life, and all worked identically, virtually no change in bias or setup procedure at all. This predictability speaks volumes for easy production, repeatable performance and long, reliable life.

TG3, I have your NAKSA ready and able on my workbench, please answer my emails!!

Thanks for the post, John, not long now......

Hugh

jkeny · « **Reply #69 on:** 7 Jul 2010, 08:19 am »

It's starting off at a nice production pace - I hope it builds form here.

Yes, it is a lucky man who finds a job that he loves doing - you just need it to generate a livelihood & you are in heaven. The feedback from happy customers is the icing on the cake.

Now, please put me out of my misery & relieve me of my senior citizen affliction, what is the term you use for people who judge everything by the numbers?

AKSA · « **Reply #70 on:** 7 Jul 2010, 08:34 am »

John,

Would that be the math 'n measure set? These guys are keen on the pscyhology of numerical appraisal, a term first used by a British engine designer in the twenties when commenting on the latest craze towards twelve cylinder engines.....

Hugh

Joe Rasmussen · « **Reply #71 on:** 9 Jul 2010, 03:13 am »

Hi Hugh

It's been a while since... Got a call from Bill (bhobba here) to alert me about your "asymmetrical" low active component count amplifier... very interesting indeed. Heretical? Hey, I know all about that!!! My website was recently said to have been "entertaining to read" on some other forum. Is that the same thing?

I know that Mike Lenehan has both your Soroya and my JLTi EL34 amps up there (Craig borrowed it?) and that they make an interesting comparison. Your comments re suppressed high odd order harmonics has long been an obsession with me, with those high order odd products buried below a sufficiently low noise floor and yet that noise floor to 'randomise' those products. Also the Jean Hiraga "cascading" harmonic distribution like a waterfall, each successive harmonic being below the one before it. He claimed he could predict much of the amp's sonic character by just looking at that spectral distribution.

Looks like I may get one of your NAKSA when available - we are arranging it. Certainly with onboard rectification, reservoir caps etc this amp looks like a DIY'ers dream - you don't make it hard to do. Just add AC.

BUT... something struck me and looking at the pic you posted reminded me of an 80's project which looked very similar - the heatsink looks almost the same but bigger still - and there was those who... bridged it. Just curious, but is it doable or does the thought horrify you? Could make a massive pair of monoblocks or two NAKSAS in a stereo amp. Worth thinking about as it may appeal to an expanded market. You get to sell twice as many to some DIY'ers.

Ahah! Just thought of a way to do it that would require no additional active circuitry. Would also provide a balanced input if required.

Mind you - bi-amping speakers with two stereo amps would also be nice.

Cheers, Joe

PS: There is something else I'd love to discuss with you... but not here... but it may suit this topic - only you will be able to tell if it does.

bhobba · « **Reply #72 on:** 9 Jul 2010, 04:35 am »

Quote from: Joe Rasmussen on 9 Jul 2010, 03:13 am

I know that Mike Lenehan has both your Soroya and my JLTi EL34 amps up there (Craig borrowed it?) and that they make an interesting comparison.

A touch of confusion here. He has heard the Soraya - I don't think he has one up there right now. When I get the NAKSA done we will certainly do a direct comparison to your JLTi EL34 - and yes it will be very interesting.

Thanks
Bill

AKSA · « **Reply #73 on:** 9 Jul 2010, 06:44 am »

Hi Joe,

Thanks for dropping in!

Yes, Craig took the Soraya to Mike's for a listen, I was not aware of the comparison with your JLTi, about which I hear very good things.

I have long preached bad thoughts about measurbators around the DIYaudio forum and been pilloried by some of the smartest guys in the room. It is difficult to discuss things with these guys as they really are frightfully intelligent, and have formed a very negative judgment well in advance. I think distortion profiles are much more significant than simple THD, which doesn't say much at all. You need to aim for the cascading waterfall, as you nicely put it, and this requires a lot of careful design, with some significant trade-offs that many are not prepared to make even though the improvement in sound quality is marked. But from my long discussions with Terry Demol, you are well acquainted with this approach and there's nothing left you could learn from me!

Bridging? Nah..... I don't recommend it, because along with the increased power comes double the current, and this must pass through the same output stage at both ends of the waveform. The NAKSA output stage is pushed hard, with a single pair on 42V rails, and to effectively bridge it you would need two pairs on each amp. The best and most economical option would be to simply build out the output stage on a NAKSA and increase the rail voltage - this would give you the added power without doubling up on power amps and requiring a transformer phase splitter.

Thanks for the post, Joe, good to see you around and enthusiastic and innovative as ever!

Cheers,

Hugh

painkiller · « **Reply #74 on:** 9 Jul 2010, 02:06 pm »

Quote from: AKSA on 7 Jul 2010, 07:49 am

Another off today, to Ken Li in LA

Are you talking about Ken Lee? http://www.youtube.com/watch?v=_RgL2MKfWTo

AKSA · « **Reply #75 on:** 10 Jul 2010, 12:20 am »

PK,

Brilliant YouTube, mein gott in himmel....... absolutely hilarious!!

No, not that guy at all, you naughty fellow......

I love wandering through YouTube looking for people doing outrageous things on motorcycles, or start-ups of old war birds, Mustangs, B29s, etc. It's fascinating watching the rich tapestry of other people's lives, isn't it?

Hugh

bhobba · « **Reply #76 on:** 10 Jul 2010, 12:34 am »

Quote from: AKSA on 10 Jul 2010, 12:20 am

I love wandering through YouTube looking for people doing outrageous things on motorcycles, or start-ups of old war birds, Mustangs, B29s, etc. It's fascinating watching the rich tapestry of other people's lives, isn't it?

Absolutely. Love it as well. Make sure you checkout the Fat Aussi Bastard - hilarious:
http://www.youtube.com/user/TheFatAussieBarstard

Thanks
Bill

James Romeyn · « **Reply #77 on:** 10 Jul 2010, 01:54 am »

Hugh
I love reading your posts and very much look forward to hearing one of your treasured amplifiers at the earliest opportunity.

Dr. Earl Geddes, someone whom I admire tremendously, discussed at DIY his proprietary amplifier test procedures. IIRC it was all well over my head.

I'd love to read your comments on Earl's amplifier test procedures (in layperson language) if you are familiar with it. Several highly technical members at DIY were impressed enough with Earl's notes that they requested he publish specifics.

Earl does not make or sell amps so I assumed this would be OK to post. Please just delete or ignore it as you see fit.

AKSA · « **Reply #78 on:** 10 Jul 2010, 01:14 pm »

Thank you James,

We shall have to reach agreement with the first SLC resident who buys one!!

I have noticed Earl's work and believe he is truly on the right track. I have not researched his papers, but agree with his notions of weighting the high, odd order harmonics in terms of 'non-musicality'. The Gedlee Index makes a lot of sense to me.

I do like the way you describe your guitars, very evocative. Did you know that Tommy, an Aussie by the way, does not read a note of music? Amazing talent, isn't it?

Hugh

James Romeyn · « **Reply #79 on:** 10 Jul 2010, 02:34 pm »

Hugh
I saw Tommy play locally. I was sitting close to a corner at the USU Performance Hall, where there was some apparent bass boost from a mode. His sound guy really cranked it up during Tommy's tribute to the Aborignal people. My L ear is still suffering some effects. You just gotta bring ear plugs no matter the performance.

No, I did not know Tommy doesn't read music, but I'm not that surprised. Robbie Robertson of The Band and Eric Clapton are completely self-taught. Robbie had a sum total one lesson with one teacher, whose favorite music was Hawaiian and he wore Hawaiian skirts. If either Robbie or Eric learned to read music it was much later in their careers after they had already made their musical mark.

I have a story on this subject: a customer, the organizer of the Django festival in Washington state, visited to pick up his Thorell guitar. The customer asked Ryan if he had considered using computer programs to assist in guitar design. Ryan, a gifted musician who won a jazz guitar award, kind of laughed a little and said that would be like Paul McCartney learning to read music.