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I have two 250k pots that I want to use for a tone and volume control. Does the rating on the pot have any bearing on the size of the cap that is wired to ground?I have seen mention of .033 to .047 caps being used, but I don't know what the difference would be, if any.I thought I read somewhere that a 250k pot would sound "warmer" than a 500k pot. Is this still true if wired to a piezo?