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From: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
Newsgroups: sci.electronics
Subject: Re: How do I choose a capacitor type ?
Message-ID: <1991Feb5.185727.14775@news.larc.nasa.gov>
Date: 5 Feb 91 18:57:27 GMT
Article-I.D.: news.1991Feb5.185727.14775
References: <64@owl.ukc.ac.uk>
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Reply-To: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
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In article <64@owl.ukc.ac.uk> abs@ukc.ac.uk (A.B.Smith) writes:
>I am currently building a number of audio circuits (pre-amps, effect
>boxes, that sort of thing) and the circuits I have don't specify the
>construction material of the capacitor.

Four coupling capacitors in audio circuits (DC blocking caps), use polyester
or polypropylene caps.  They'll be a bit hard to find in large values, but
the audio mail order places carry them and you'll be shocked at the improvement
in sound over cheap electrolytics.  For power supply caps, use good quality
electrolytics.  The high frequency types designed for switching supplies are
good; they have low ESR which permits them to deliver a lot of current fast
on demand, which is important for even small signal audio stuff.  You'll find
capacitors contribute a lot to the sound quality (and resistors contribute a
lot to the noise figure).
--scott