"As with the entry-level ACA, what happens when you send the lowest signal level through a 10 uF electrolytic cap, and the highest signal level, at the output, through a 4,700 uF electrolytic cap ?? "
Mr. Medwin, I am not a designer I have only basic knowledge about electronics so could you explain what happens in this situation?
Capacitors, fidelity wise, are probably the worse part in audio, to send an in-series signal through. The worse sounding, most harmful capacitors, are electrolytics. Films are usually much better, but they are limited in their uF size, and a less than ideal compromise when placed in - series with the signal. Avoid them, when ever possible.
There today
ARE higher quality electrolytics made, specifically to tackle in-series applications. But the very best of these, will have a hard time sounding natural, VS a good film, or a well executed
multiple-value conglomeration of film capacitors.
SO Kannan........... the very best answer to this is NOT to employ
any in-series capacitors in a design, if possible, be it a film OR worse, any electrolytic.
The ideal is called Direct Coupling, a short piece of highest - quality wire connecting the amplified signals, which will exhibit the least degrade, and maintain the most intact naturalness of the music's signal. Got that ??
( I personally do this with two - stage directly- coupled low power tube amplifiers, I design and build - mostly for myself. )
"What sort of ultimate-level fidelity ...... can you achieve?? "
Easily, the best reproduced sound you will have ever experienced, not perfect, but jaw dropping. The REAL test is the amp being, not boring, but
mentally-stimulating long-term.
Can ultimate fidelity be achieved with such a simple design?
No, never with
solid state and simplicity.
Extra care and design-thought must be applied to an entire design. THE most important aspect of any design is how well the Power Supply, feeding voltages to the different stages in the amp, is designed and executed.
Most amps do severely falter, right there.
to my understanding, Nelson Pass created the ACA design for beginners who needs a simple and easy amp to build. And i doubt someone will use ACA as their ultimate amp.
Agreed. But for me, since my first all-triode amp's design in 1980-1982, I have always
tried to build an ultimate amp.
It has always been " a goal ", even if I have no formal E.E. background !!!
Will " good enough " be long-term OK for you ??
no, could you suggest some solid-state designs which have few components like this, are easy to build, uses simple ps, and offers ultimate fidelity?
Sadly, NO.
It does not exist. In life, we should not ever expect to get something for nothing !!!
My first Audio Mentor in 1980 once
taught me : " Jeffrey,
in the end, we all listen to a music-modulated power supply. How good is it ?? " Besides the power supply, the amp can not use Negative Feedback.
ONLY then, do you stand
a chance for listening excellence.
But know this : the better zero NFB solid state amps, as reported to me by their owner, eg: a Nelson Pass zero NFB
SIT3, is
beaten badly I am told, by my DIY tube amp execution. A design I've detailed here on HFV already. Performance - counts !
There is not a solid state amp I have personal experience with that I can recommend, that I can afford, and that I would employ.
Jeff Medwin
