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From: mips!mips.COM!mark@decwrl.dec.com (Mark G. Johnson)
Newsgroups: rec.audio.high-end
Subject: Re: Trimming MSB on DAC
Message-ID: <2627@uwm.edu>
Date: 27 Feb 90 14:20:02 GMT
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In article <2589@uwm.edu> @sun.acs.udel.edu:hamilton@sun.acs.udel.edu (hamilton) writes:
>
>I read in the current issue of CD Review that it is possible to adjust the 
>trim pots on the D-A convertors of a CD player to improve linearity.
> ...  Linearity below -100dB is
>something found only in the most costly CD players, and maybe in the new
>1-bit machines.  Does anyone know what is needed to perform the adjustment?
>Can it be done by the average joe?

Isn't the human ear an acceptable test instrument?  It would appear that
either (i) the ear can't hear these effects, in which case adjustment is
unnecessary;  (ii) the ear can hear them, so adjustment by ear is
praciticable.  You could even try it a week at a time at each of ten
equally-spaced positions on the dial, thereby getting the advantage of
long-term exposure and relaxed listening on a wide variety of musical
signals -- not just test waveforms.
-- 
 -- Mark Johnson	
 	MIPS Computer Systems, 930 E. Arques, Sunnyvale, CA 94086
	(408) 991-0208    mark@mips.com  {or ...!decwrl!mips!mark}