The "greater than the DC voltage it will see, plus at least 20% spare" would
be the first rule. Be aware that a capacitor can see more than the power
rail voltage in some circumstances (i.e charged in one direction, then
having the opposite voltage applied it). Double the DC voltage is good. The
value specified on the circuit diagram (if present) is ideal.
Ken
_______________________________________________________________________
Ken Stone
sasami@... otherunicorn@...Modular Synth PCBs for sale <
http://www.cgs.synth.net/>
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