MOSFET Fuzz & Distortion Circuit PUBLIC

MOSFET Fuzz & Distortion Circuit for Electric Guitar

MOSFET fuzz and distortion circuit for 6-string electric guitar. 2-Voiced DMOS fuzz (depletion-mode MOSFETs) plus CMOS op-amp distortion (complimentary MOSFET, meaning MOSFET input stage with BJT output stage, internal to op-amp), and active 3-band tone. Controls Include: Drive 1, Gain, Fuzz 1 enable switch, Fuzz 1 symmetry switches, Fuzz 1 Depth, Fuzz 2 enable switch, Fuzz 2 symmetry switches, Fuzz 2 Depth, Drive 2, Drive 3, Bass, Mid, Treble, and Volume. IC1 is a dual FET-input op-amp IC chosen to ensure clean operation of the Input and Output stages. IC2 is a dual CMOS op-amp IC chosen to provide tube-like distortion when overdriven. Fuzz comes from four dual DMOS devices (DMOS = depletion-mode MOSFETs), which provide tube-like clipping; one pair in a soft-clipping (feedback type) array, and the other pair in a hard-clipping (shunt type) array. Range at or above 0 dBV is from 57 Hz to 20 kHz. Suitable for 6-string guitar in standard tuning. [Not suitable for 7/8-string guitar or bass-guitar.] Maximum gain = +20.8 dBV (Vo/Vi = 11) @ 1 kHz with all controls at 50%, or +67 dBV (Vo/Vi = 2239) with all controls at 100%.
Do not use the circuit with all controls at 100% except briefly as a worst-case scenario during breadboard testing. Power-supply not shown. Requires a regulated dual-polarity DC supply providing +-9VDC or +-12VDC or +-15VDC at >= 50 mA of current. And while simulator verified, treat the circuit as experimental in nature. Breadboard test it before committing to a soldered build.