Negative, i have several Aksa models..no one of them sound bad
The opposite.... they sound very well...some models are awesome.
Carlos
The opposite.... they sound very well...some models are awesome.
Carlos
After some time spended on the amplifiers I am comming to the same conlusion. When I am working on some projects I always try to measure them to find the connection between the measurement resaults and ''the nice sound''.
The measurements can confirm if the amp is designed well and is safe but not all has to be allways right by the book.
I can give a very simple example as bellow (overloaded casode VAS), the measurement can suggest that amp will be a crap but the sound was really so relaxing that I could listen to it all the time.
Attachments
bimo
Yes You are right but please explain me why some of the amps is difficult to listen for more than few hours because top octave (10kHz-20kHz) is too much ''sharp'' and ''pointy'' even if they measures very well and some of them are very good in measurements and have very smooth and delicate top octave.
thx
Yes You are right but please explain me why some of the amps is difficult to listen for more than few hours because top octave (10kHz-20kHz) is too much ''sharp'' and ''pointy'' even if they measures very well and some of them are very good in measurements and have very smooth and delicate top octave.
thx
Borys,
You touch on psychoacoustics, the way the human animal perceives and 'enjoys' music. It is a different discipline and not well understood by the purist technologists. When you consider the psychology of numerical appraisal (a behaviour we all seek with better figures, without regard for WHAT the measurements correlate) it is very difficult to avoid the OCD pursuit to, ahem, reducing THD <0.0003%. The figures, the figures, that is the matter........
Consider the marketing machine, and even the DIY forums. All these 'institutions' are properly set up around measurement, accuracy, objective assessment, commercial arenas, and tradition. Any new idea always has a hard time for years to change the tide, and there is no shortage of criticism from 'experts' - and commercial status quo. These issues are major issues, but they are hidden, behind the cover.
All this is conjecture, subjective, abstractive. I'm embarrassed to mention it, but it need to be thought about.
Hugh
You touch on psychoacoustics, the way the human animal perceives and 'enjoys' music. It is a different discipline and not well understood by the purist technologists. When you consider the psychology of numerical appraisal (a behaviour we all seek with better figures, without regard for WHAT the measurements correlate) it is very difficult to avoid the OCD pursuit to, ahem, reducing THD <0.0003%. The figures, the figures, that is the matter........
Consider the marketing machine, and even the DIY forums. All these 'institutions' are properly set up around measurement, accuracy, objective assessment, commercial arenas, and tradition. Any new idea always has a hard time for years to change the tide, and there is no shortage of criticism from 'experts' - and commercial status quo. These issues are major issues, but they are hidden, behind the cover.
All this is conjecture, subjective, abstractive. I'm embarrassed to mention it, but it need to be thought about.
Hugh
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Accurate is ideal term, and none of any amplifier is accurate 😀
But if your sound system make you believe that the sound is real (may be it sound good or not, example: my voice is not sound good) then it is accurate.
Sound good is subjective, it is matter of taste. Many people in my country want strong bass that can shake his chest and bones and do not care about distortion. Many of them do not realize when clipping occur 😱
Borys.
I discovered many years ago that amplifiers that have vanishingly low measured distortion can often sound clinical, hard and a bit fatiguing- but not always! I think that there is something going on for which there is no defined measurement as to an amp's perceived "niceness" factor. Only the human animal is capable of this, and It's very hard to describe in real terms.
Many years ago, Hugh paid me a visit when I was mucking about with an Australian designed Digi-125 amp kit, so we did a bit of brainstorming on it and the original AKSA55 was the end result. When I said "brainstorming", Hugh was the brains- I just stormed a little!
Now I have an amp design called the Quasimodo, and this was the result of much experimentation and listening but with no 'scope involved at all 😱 Just a multimeter and a fair amount of input from Hugh. I must point out that I have never measured the Quasimodo, nor even used the Spice program 😕 No, but there was hour upon hour of tweaking, listening, tweaking, listening, etc, etc and then more of the same....!
Edward Rotgans of Adelaide Speakers now uses an 80 watt per channel Quasimodo as his reference amp, taking over from an SGR he used previously!
Quasimodo Stereo Amplifiers
And Bimo, you are totally correct, no amplifier is ever 100% accurate! The only accurate means of listening to music is live non amplified instruments and singer/s- as soon as an amplifier is introduced, the music is no longer "live" but a reproduction! Of course, rock bands can not exist without amplification, but they ain't exactly a "natural acoustic" event.
I know that I will receive some flak over those last statements, but it needs to be said. There is no such thing as an accurate sound system- some may give the illusion of accuracy, but you just can't beat the real thing.
Go listen to a full symphony orchestra playing flat out- no domestic system can come near it!
The best we designers can do is to make the musical experience in the home as enjoyable as possible, and that is Hugh's goal as it is mine.😀
Mind you, I wonder if many audiophiles have ever actually heard a symphony orchestra live. If they did, they would probably find fault with the venue's acoustics or complain about "background noise", that is, the audience!
Maybe they might take along an AP1 to measure the THD.....?! Ya gotta have a laugh sometimes!😛
I discovered many years ago that amplifiers that have vanishingly low measured distortion can often sound clinical, hard and a bit fatiguing- but not always! I think that there is something going on for which there is no defined measurement as to an amp's perceived "niceness" factor. Only the human animal is capable of this, and It's very hard to describe in real terms.
Many years ago, Hugh paid me a visit when I was mucking about with an Australian designed Digi-125 amp kit, so we did a bit of brainstorming on it and the original AKSA55 was the end result. When I said "brainstorming", Hugh was the brains- I just stormed a little!
Now I have an amp design called the Quasimodo, and this was the result of much experimentation and listening but with no 'scope involved at all 😱 Just a multimeter and a fair amount of input from Hugh. I must point out that I have never measured the Quasimodo, nor even used the Spice program 😕 No, but there was hour upon hour of tweaking, listening, tweaking, listening, etc, etc and then more of the same....!
Edward Rotgans of Adelaide Speakers now uses an 80 watt per channel Quasimodo as his reference amp, taking over from an SGR he used previously!
Quasimodo Stereo Amplifiers
And Bimo, you are totally correct, no amplifier is ever 100% accurate! The only accurate means of listening to music is live non amplified instruments and singer/s- as soon as an amplifier is introduced, the music is no longer "live" but a reproduction! Of course, rock bands can not exist without amplification, but they ain't exactly a "natural acoustic" event.
I know that I will receive some flak over those last statements, but it needs to be said. There is no such thing as an accurate sound system- some may give the illusion of accuracy, but you just can't beat the real thing.
Go listen to a full symphony orchestra playing flat out- no domestic system can come near it!
The best we designers can do is to make the musical experience in the home as enjoyable as possible, and that is Hugh's goal as it is mine.😀
Mind you, I wonder if many audiophiles have ever actually heard a symphony orchestra live. If they did, they would probably find fault with the venue's acoustics or complain about "background noise", that is, the audience!
Maybe they might take along an AP1 to measure the THD.....?! Ya gotta have a laugh sometimes!😛
😎
Now, I learn how to design an amplifier that make me think and feel it is accurate 🙂
Many years ago I measure my amp when I was an engineer. And I am proud about the result and then I abandon this hobby and play with microcontroller. But when I built VSSA variant which in simulation on won by it slew rate then my amp, I think again about measurement of an amplifier. What minimum or maximum parameter of each specification that must be achieve? What is the receipt?
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I have to say I had read a lot about the desirability of low feedback and the undesirability of high feedback. But after I built my TGM8 it all became very clear, accurate, musical (and very pleasant) - that feedback when used well can be your best friend.
Did anybody make PCB's for the AKSA clone / Baby AKSA or similar? ARE PCBs available from anyone? I need a good amp for the TV set, one for the bedroom, one for the children's room etc so I am interested in (up to) 12 mono PCB's. Anyone?
Greg made a small batch of PCB's. I don't think he made any gerbers available I can't remember if there was any artwork or not in this thread.
I got some boards I designed (not for Baksa) done by itead studio and was very happy with them ITEAD Studio 2Layer Green PCB 10cm x 10cm Max These are dual layer boards (I think Greg's were single sided, I have a pair somewhere along with output transistors, but I've not got around to making my Baksa yet)... I can't remember the size but they may well be within the 10 X 10cm size.
edit: there was artwork 🙂 http://www.diyaudio.com/forums/solid-state/168554-based-hugh-deans-aksa-55-a-2.html#post2218663
Tony.
hi, i made this pcb but i wanna use 20v ish psu since my speakers are high efficiency and i already have 25v caps available. what resistors do i need to tweak for the different psu voltage?
i'm guessing r3, 4, 5 to lower values?
i'm guessing r3, 4, 5 to lower values?
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I am about to release a built/tested module of the Super AKSA.
This is the first time I have reinvented the original amp; this new amp, which will be available in two months, incorporates all the knowledge I have learned in the last 16 years, and it is a pearler. Quite the best AKSA ever, and it will replace the NAKSA 80.
The Super AKSA, the SAKSA, features powerful, driving bass; zero thump at switch on/off; rich, resolving midrange and clear, utter noise free top end. Watch my website for this..... but I should tell you it will be a module, built/tested, and sold with warranty.
Hugh
This is the first time I have reinvented the original amp; this new amp, which will be available in two months, incorporates all the knowledge I have learned in the last 16 years, and it is a pearler. Quite the best AKSA ever, and it will replace the NAKSA 80.
The Super AKSA, the SAKSA, features powerful, driving bass; zero thump at switch on/off; rich, resolving midrange and clear, utter noise free top end. Watch my website for this..... but I should tell you it will be a module, built/tested, and sold with warranty.
Hugh
I admire your passion for audio and your knowledge. now I feel at this age you are super fast in releasing new amplifier super AKSA . just now you released maya 200 . I have a dream one day I will own one of your amplifiers and I will.
Not so fast Suresh! I spent a year on the Maya, and just finished about six months on the SAKSA!
The connection between the schematic, the dimensioning and the subjective listening is very tenuous and takes years to apprehend, if at all. Most designers don't agree with each other at all, and most work in a vacuum. Many of my amps have two, three or four people's thoughts in them. The 'tricks' are not the same between designers; I work with distortion; simply try to design which emphasizes the even order harmonics whilst reduces the odd orders. Even so I'm not dead sure this is the best way; transient behaviour in an amp is very important and not well understood even today. You need to be a detective rather than a scientist, and of course there is a lot of listening sessions and you need to have four or five listeners, not just yourself.
But it's fun, thankfully at 65 I still love it as much as I started out at 45.
Cheers,
Hugh
The connection between the schematic, the dimensioning and the subjective listening is very tenuous and takes years to apprehend, if at all. Most designers don't agree with each other at all, and most work in a vacuum. Many of my amps have two, three or four people's thoughts in them. The 'tricks' are not the same between designers; I work with distortion; simply try to design which emphasizes the even order harmonics whilst reduces the odd orders. Even so I'm not dead sure this is the best way; transient behaviour in an amp is very important and not well understood even today. You need to be a detective rather than a scientist, and of course there is a lot of listening sessions and you need to have four or five listeners, not just yourself.
But it's fun, thankfully at 65 I still love it as much as I started out at 45.
Cheers,
Hugh
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