“This unique fuzz tone is an octave fuzz using two germanium diodes to produce the square wave clipping. The controls are ‘Balance’ (volume), ‘Expander’ (fuzz amount), a two position ‘tone’ switch, and an on/off foot switch on top. There are two unique features of this device that set it apart from other distortion and fuzz pedals.”
“The first is that the full-wave rectification of the circuit produces an upper octave as well as a slight lower octave. This also gives the sound a lot of compression and gives a mild ring modulator effect. The second unique feature is a tone switch that engages a 1khz filter that “scoops” the mids, giving a very fat, almost bassy tone, unique to this circuit.”
A great Who website with a lot of good information on this effect as well as killer Who tab.
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