ok...so I'm doing a keeley-style mod to my Boss DS-1 and I have a question about capacitors. they come in ceramic and film materials and I was wondering what the difference was (audibly speaking) if there is any. any help is appreciated

I typicall avoid ceramic. They are noisy. If it is a very small value capacitor (in the pF range) I use silver mica. Any other value up to 1 uf (or mf) I use poly-film.
ceramic is supposed to be noisy and the general type to use is polyester film or metal film, which is what I think Robert Keeley uses.
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