Phillip, I recently received an email from a friend of mine, who's knowledge I respect greatly. He has a 1967 Clyde McCoy wah pedal with all original parts and he listed the capacitors for me. This is what he wrote:
2-ducati 10,000pf
2-tropical fish capacitors
1-ducati gold electrolytic 4uf 15volts bipolar.
I was sure that the last capacitor was np. Everywhere on the net, that I have checked says np. I have questioned my friend and he said he was looking at and reading bipolar right from the gold electrolytic capacitor. As I am starting my own Clyde reproduction, I really need some advice here. I am probably missing something. I don't want to beat a dead horse, just really confused.
They probably used just about any capacitors that they could get their hands on cheaply back then. It's not uncommon to see the exact same pedal model with several different parts between individual units. The McCoy is a prime example. Some had 33K resistors paralleling the inductor, while other had a 100K resistor paralleling the inductor.
Like I've said before, that particular capacitor won't make any difference in the sound of the pedal at all. You could use a 4uF NP, bipolar, electrolytic; or you could also use a 4.7uF NP, bipolar or electrolytic. There won't be any difference in sound.
