"John Atkinson" wrote in message
om

(Audio Guy) wrote on r.a.h-e in message
...

Audio is a trivial application, they learn about power supply
design and amplification, which is pretty much all there is to
audio amplifiers, in their early years and then go on to much more
interesting and challenging concepts.

I see statements like this from time to time, yet I am not so sure
that audio design is "trivial."

One of the better online discussions of audio power amp design is posted at
http://www.dself.dsl.pipex.com/ampins/dipa/dipa.htm . Not trivial, but also
no longer any kind of big secret for people who do their homework.

There are not many other design fields
where an amplifier: has to provide up to 30dB of voltage gain; act as
a voltage source into a wide and arbitrary range of load impedances
and do so in an unconditionally stable manner; have a passband noise
contribution at least 90dB down from 1W into 8 ohms, no matter what
its voltage gain and ultimate power delivery; have distortion
components under all load conditions that are below the threshold of
hearing no matter what the program material is; and do all the above
over at least three-decade, ie, a 10-octave passband.

However, for $5 or $10 you can buy one-up, a chip that delivers very usable
amounts of power with very little or no audible distortion and just a few
added parts. However, turning this chip into a competitive product is still
a goodly amount of work.

Thoughts, gentlemen? I would suggest that designing, say, a typical RF
amplifier is, by comparison, "trivial" but, of course, I may just be
missing something :-)

Any project that involves designing and/or building and selling a
competitive product is challenging. Even the experts fail at it, every once
in a while.