RO "MarvelMOS" Distortion Circuit PUBLIC

Richter Original "MarvelMOS" Distortion Circuit for Guitar

Richter Original "MavelMOS" distortion circuit for guitar or bass, with all-discrete MOSFET circuitry, 3-band Fender-style tone-stack, and shunt-type Schottky-diode fuzz. Controls Include: Input Level, Bass, MId, Treble, tone-stack Sum, Drive, Fuzz enable switch, Fuzz symmetry switches, Fuzz Depth, and Volume. Uses two dual enhancement-mode N-channel MOSFET chips. M1a can overdrive M1b which can overdrive M2a which can overdrive M2b, depending on control settings, not counting the fuzz effect. Extremely broad bandwidth. Frequency Range 20 Hz to 30 kHz with all controls at 50%, or < 20 Hz to > 40 kHz with all controls at 100%, with or without fuzz. Suitable for 6/7/8-string guitar or 4/5/6-string bass. Modest gain. Maximum Gain = +5.6 dBv @ 2.5 kHz with all controls at 100%, or >= +47 dBV above 10 kHz and +36 dBV @ 20 Hz with all controls at 100%. Fuzz has little to no effect on overall gain with controls at 100% but significant effect (cuts > 3 dBV) with controls at 50% or lower. Circuit can be for stomp-box or rackmount projects. The battery can be replaced by a regulated single-polarity DC supply providing +9vDC or +12VDC at >= 40 mA of current. And though simulator verified, treat the circuit as experimental. Thoroughly breadboard test before committing to a soldered build. House in a grounded metal enclosure.