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From: spp@zabriskie.berkeley.edu (Steve Pope)
Newsgroups: sci.electronics
Subject: Re: How do I choose a capacitor type ?
Message-ID: <10836@pasteur.Berkeley.EDU>
Date: 6 Feb 91 19:12:43 GMT
References: <64@owl.ukc.ac.uk>
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Reply-To: spp@zabriskie.berkeley.edu.UUCP (Steve Pope)
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In article <64@owl.ukc.ac.uk> abs@ukc.ac.uk (A.B.Smith) writes:
>
>
>Hi,
>
>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.
>
>Could someone give me a few rules on what sort of capacitor I should
>select (ie. when should I use Ceramic, Mylar, Polyester, etc).

A few simple rules for audio circuits:

(1) Always use an aluminum electrolytic as opposed to a tantalum 
in an audio signal path (this applies not only to coupling caps,
but emitter bypass caps etc.).

(2) Polypropylene or polystyrene are good choices for equalizers
and such where some precision is needed.

(3) Don't use a capacitor with high hysteresis (such as a ceramic)
as a sampling cap in a sample/hold circuit.

/steve