The ‘Fuzz’ sound is derived by clipping the input waveform, there by enriching the signal with odd harmonics which provide The harsh sound. This circuit produces a fuzz which gradually decays into a ‘clean signal’.
The circuit uses the standard op-amp 741 in non-inverting configuration. The gain of this amplifier is com rolled by the feedback network comprising VR1, R2 and R3.
Input signal from the guitar passes to the op-amp through DC blocking capacitor C1. Resistor Rl sets the input impedance at 100k, which suits most guitars, Resulting signals from the op-jimp are reduced in amplitude by the potential divide action of R6 and R7, giving an attenuation factor approximately four. Thus the maximum output signal via capacitor C3 available lor inputting to an amplifier is about 150 mV. This level is maintained during the period of clipping (fuzz) and then decays naturally to zero.
A foot-switch may he used to bypass the signal whenever required. The whole circuit can be assembled on a general-purpose PCB. A red LED can be used to indicate that the `‘Fuzz Effect’ is ‘on’ by coupling it to the bypass switch suitably. This unit is powered by 8V PP3 battery.