"Eeyore" wrote in
message
Arny Krueger wrote:
"Kevin McMurtrie" wrote
(Martin Schöön) wrote:
Anyone here with firsthand experience of amplifiers
based on Tripath's ICs?
For example:
http://www.41hz.com/
I haven't used them personally but I read their sample
schematics and docs. They're not audiophile but they're
nothing to worry about for the MP3 generation. Their
primary feature is enabling ultra-compact amplifiers
with low complexity and cost.
The irony is that the Tripath amp I have, which is based
on their TA2020 chip and a few discrete transistors, is
neither smaller nor cheaper, nor simpler than a
comparable linear amp would be. The parts count and
size is inflated by the low pass filter on the outputs.
The heat sinks are tiny, but everything else is pretty
much regular-sized. The output filter network is almost
half the amp, and is loaded with inductors that were no
doubt not free.
Sure, but it'll use less power than a linear amp.
In most office and home applications that's not an issue. Even in mobile
applications like a car, there's plenty of power available.
That's
a main reason why switching amps have become popular,
although I note that the supposed popularity seems to
have waned recently.
I see using them in cell phones. I don't think they have gone anywhere with
portable music players.
I was SERIOUSLY considering Tripath for a new product
back around 2000 but I wasn't impressed by the
demonstration where I wanted to run it at its full power
sine wave rating
The Tripath module I have was rated well optimistically.
but the rep said the demo amp wasn't
designed to cope with that ! What the hell were they
thinking of ?
The problem I saw was that ignoring your first nasty bit of news, the amps
had a lot of nonlinear distortion related to the switching, well below
clipping. I mean like 2-3 dB below clipping. They also had a relatively
high output impedance in the top half of the audio band.