Extreme Op-Amp Distortion + Boost PUBLIC

Extreme Op-Amp Distortion + Diode Fuzz + Distortion Boost

An extreme distortion circuit using overdriven op-amps for distortion, a shunt-type Schottky-diode array for fuzz, an extra op-amp gain stage for distortion boost, and 3-band active tone. The op-amps chosen provide a clean signal from the Clean Stage but tube-like distortion from the Distortion Stage, with both signals mixed at the Tone Stage (which also gives tube-like distortion if overdriven). The Boost Stage affects only the distortion / fuzz signal. Controls Include: Master Drive, Clean Gain, Clean Level, Distortion Gain 1, Distortion Drive, Distortion Gain 2, Distortion Level, Boost enable switch, Boost Gain, Fuzz enable switch, Fuzz symmetry switches (two, with two settings each), Fuzz Depth, Bass, Mid, Treble, and Volume. Overall Frequency Range between -3 dBV corners not boosted is 25 Hz to 10 kHz with all controls at 50%, but 25 Hz to 12 kHz boosted. Suitable for 6/7/8-string guitar or 4/5/6-string bass. Caution! High-gain circuitry. Maximum Gain not boosted is +20 dBV @ 1 kHz with all controls at 50%, but +32 dBV @ 1.6 kHz boosted, and over twice each with all controls at 100%. [Do not use the circuit with all controls at 100% except as a brief worst-case scenario during breadboard testing.] If ICs are to be substituted, keep IC1 as is or use a pin-compatible substitute with the same or better noise figures and the same or higher input impedance. For IC2 or IC3, any substitute is allowed. Examples: For JFET distortion, use a TL082CP, or for MOSFET distortion, use an OPA2156IDR. Power-supply not shown. Requires a regulated dual-polarity DC supply providing +-9VDC or +-12VDC or +-15VDC at >= 60 mA of current. And though simulator verified, treat the circuit as experimental. Breadboard test before soldering. House in a grounded metal enclosure.