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From: portal!chan@uunet.UU.NET (Jeff Chan)
Newsgroups: rec.audio.high-end
Subject: Re: Amplifiers, "Audio Amateur", etc.
Message-ID: <8615@uwm.edu>
Date: 31 Dec 90 15:09:38 GMT
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Originator: tjk@csd4.csd.uwm.edu

In article <8546@uwm.edu> henry@ginger.sri.com (Henry Pasternack) writes:
>
> [Henry speaks about Audio Amateur & Speaker Builder...]
>
> [...] A relative newcomer to
>the publication is William Chater.  Chater has a very systematic
>approach to his designs, and presents a lot of decent measurements.
>He has developed an all-MOSFET power amp and preamp.  Look for the
>40W amplifier in 2/3:88 and the preamp in 1/2:90

Has anyone on the net built or heard the Chater amp?  I've got a 
pair of the boards and plan to build them as mono amps with regulated
power supplies.  I'll probably make some of the mods suggested
in the follow-up letters of Chater and others, such as:

  o  rf filters and surge limiters on the ac power 
  o  a snubber cap across the power switch
  o  greater use of film caps (though the signal path is DC coupled 
        except for one (~optional) blocking cap at the input)
  o  possibly deleting or mod'ing some of the safety things like
	bypassing with caps the power supply fuses to the boards 
  o  possibly replacing the IRFD110 MOS input transistors with NTE458
	JFETs for lower noise
  o  power supply regulation using a Ryan/Staggs-like circuit

I have little doubt that this combination will sound pretty good.
(Nothing like a little golden-ear self-fulfilling prophecy. ;^) ;^) ;^)
'Course my cobbled together Magnavox mods did turn out rather 
well according to others who have heard them (and me).)

Does anyone have any comments on construction or sound of this
amp ("stock" configuration or otherwise)?
-- 

Jeff C.                                      
Internet: chan@portal.com     Usenet: {apple, pyramid, sun}!portal!chan
I am a guest at Portal.  Any opinions expressed are not necessarily Portal's.