[sdiy] VCO saw integrator cap questions

[Byron G. Jacquot]

>After 18 months of synth diy, I must confess that I'm still fairly confused
>about caps in general.  People say to use this or that cap for this or that
>application, but I'm not really sure why.  I understand that one would want
>low leakage for a sample and hold application, but other than that, I'm more
>or less in the dark.  Is there a good source of straight dope on the
>selection of caps with specific properties for specific applications? 

Here's the best we've got, written by a long time regular:
http://www.muzique.com/cap_faq.htm

Essentially, you need to know which parameters matter in an application, which caps exploit those parameters, and are available in suitable values.  Having the most stable, least parasitic cap doesn't mean much if it only comes in 10 pF.

Byron Jacquot