It seems that guitar fuzz boxes have been around since the beginning of rock, and have seen little improvement over the years. This one is somewhat different because rather than simply distorting the sound, it also pulses in step with the peaks of the waveform from the pickup because of the Schmitt trigger op amp circuit.
Capacitor C2 requires some explanation. It should normally be a 1- or 2-ÂµÂ¥ electrolytic capacitor. However, we show the value as 470 pF because it's recommended as an experimental value giving far out effects.