RO Highly Tweakable Distortion Circuit PUBLIC

Richter Original Highly Tweakable Distortion Circuit

Richter Original highly tweakable Distortion circuit for guitar or bass. Controls Include: Input Level, Input Gain, Bass Boost, Fuzz 1 enable switch, Fuzz 1 A/B switch, Fuzz 2 enable switch, Fuzz 2 A/B switch, tone Center, Bass, Mid, Treble, stack Sum, Output Gain, and Volume. Four fuzz voices. Diode Matrix 1 is in the feedback loop of IC1a and involves diode Array 1A, using LEDs, and diode Array 1B, using Schottky diodes, with both arrays symmetric; for the best-sounding feedback-type clipping. Diode Matrix 2 has shunt-type diode arrays, with diode Array 2A using standard silicon diodes, and diode Array 2B using MOSFETs wired to act like diodes, while both arrays are asymmetric, to enhance even-order harmonics. Expect the LEDs to provide bright distortion, the Schottky diodes mellow distortion, the standard diodes vintage-style hard-clipping distortion, and the MOSFETs tube-like distortion. Note that the Bass Boost control has a more pronounced effect on both gain and bass response than the Input Gain control, and the Center control has more influence on tone than the tone-stack. Frequency Range 22 Hz to only 1.6 kHz with all controls at 50%, but 12 Hz to 66 kHz with all controls at 100%. Suitable for 6/7/8-string guitar or 4/5/6-string bass. Maximum Gain = +19.6 dBV @ 100 Hz with all controls at 50%, or +41 dBV @ 250 Hz and 10 kHz with all controls at 100%. Power-supply not shown. Requires a regulated dual-polarity DC supply providing +-9VDC or +-12VDC or +-15VDC @ >= 30 mA of current. And though simulator verified, treat the circuit as experimental. Breadboard test before final soldering.