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From: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
Newsgroups: sci.electronics
Subject: Re: Digital pots (request for info)
Keywords: pots, potentiomemters, audio
Message-ID: <1991May28.145602.2798@news.larc.nasa.gov>
Date: 28 May 91 14:56:02 GMT
References: <1991May25.232651.11094@leland.Stanford.EDU>
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Reply-To: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
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In article <1991May25.232651.11094@leland.Stanford.EDU> masaki@elaine13.Stanford.EDU (Pixel) writes:
>  I seem to recall that a few months back, digital volume controls were
>discussed in this newsgroup.  I'm sorry if this is bringing up a dead
>subject, but does anyone know a company that makes or sells digitally
>controllable potentiometers which are of suitable quality for high
>quality audio production. (I'm designing part of a sound mixing console.)
>  Thanks for any help you can give me.

   I, as resident audio fanatic, suggest not using the CMOS volume control
circuits which are so ubiquitous in consumer audio gear, because, quite
frankly, they sound bad.  Your best bet for quality is to use an 8-bit D/A
and use the output to drive an OTA.  The National Semi transconductance
amps are probably your best bet.
   Still, you'll get lower noise from a mechanical stepped attenuator :-).
--scott