From: "Pacific Freight"
Subject: Re: modeling a water cooling system
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Date: Wed, 23 Oct 2002 13:33:00 GMT
NNTP-Posting-Date: Wed, 23 Oct 2002 23:33:00 EST
Organization: Comindico Australia - reports relating to abuse should be sent to firstname.lastname@example.org
Being an audiophile myself, while I can appreciate not worrying about the
lost heat in exchange for superb amplification, I can't understand why
someone would want to invest a fair chunk of money for some hard to get
resistors etc. to make one of these amps.
The distortion specs are poor, the author himself states that the sound is
not that brilliant, and I haven't done the calculations, but with such a
high current drain from the PSU, you would need some absolutely huge filter
capacitors to keep the hum down to a minimum. (1 Farad per rail??)
Class A amplification is great, don't get me wrong, but this design is
really not the best to go for if you want good sound. There was a 15W Class
A amp design in Silicon Chip (July 98) years ago. Now that was a beauty. Not
simple, not efficient, and probably not that cheap, but at least it had good
specs. From memory distortion was something like 0.00004% (They mentioned
that it was so low that it was tricky to measure with their equipment)
And that amp had a separate mosfet regulated power supply that didn't need
huge filter caps.(Aug 98) (a must for high current low noise applications
like this one)
Seriously, the amps on that site look really great. Big and professional.
With my favourite blue power lights!! But sound good? No.
"Phil Allison" wrote in message
> "Bill Sloman" wrote in message
> ** Bill, have you looked at the "zen" amp itself and why the
> dissipation is so high ?
> The whole project is completely loony tunes.
> . . . . ................ Phil