Modified Octaver-Fuzz Circuit PUBLIC

Highly-Modified Octaver-Fuzz Circuit

Highly-modified "Octaver-Fuzz" Guitar Effects Unit attributed to ETI Canada, 1980. The original circuit is available online. https://www.montagar.com/~patj/geuoctv.gif Controls in this mod include: Input Gain, Direct Send, Fuzz + Octave enable switch, Fuzz or Fuzz + Octave selector switch, Fuzz level, Fuzz Tone (tone applies only to fuzz), Octave level (octave always includes fuzz), and Volume. Intended for the 6-string electric guitar but suitable for 6/7/8-string guitar or 4/5/6-string bass because lows always extend to 25 Hz regardless of mode. 3 modes; (1) direct signal only, (2) direct + fuzz, or (3) direct + fuzz + octave. Gains and ranges per mode; (1) max. gain = +13.8 dBV @ 160 Hz, range to 1.6 kHz, (2) max. gain = +14 dBV @ 1 kHz, range to 16 kHz, and (3) max. gain = + 15.4 dBV @ 1.6 kHz, range to 16 kHz. Notice that mode gains are fairly close to each other (within 2.4 dBV) but ranges vary significantly. No tone-controls except simple tone-pot for the Fuzz effect, which is described as a "chewy" vintage fuzz, obtained from silicon diode clipping. Recommend using a tone-control circuit of some kind before or after this circuit (or both). Power-supply not shown. Requires a regulated dual-polarity DC supply providing +-9VDC or +-12VDC or +-15VDC at >= 40 mA of current. Note: Higher supply voltage results in lower op-amp noise. And while simulator verified, treat the circuit as experimental. Breadboard test before soldering.