Single-Battery Preamp 6 PUBLIC

Guitar preamp powered by a single 9V battery, with two Gain controls, Bass Boost circuit, and adjustable Schottky-diode fuzz.

Guitar preamp powered by a single 9V battery, with two Gain controls, a Bass Boost circuit, adjustable Schottky-diode fuzz circuit, and 3-band Fender-style tone-stack. Controls Include: Input Attenuation enable switch (Attenuate or Direct), Attenuation control, Gain 1, Bass Boost enable switch, Bass Boost boost/cut control, Bass Boost Level control, regular-Bass, Mid, Treble, Stack Sum, Fuzz enable switch, Fuzz symmetry switches (two with 2 settings each), Gain 2, and Volume. Range above 0 dBV is from 60 Hz to > 20 kHz, with emphasis on highs from 1 kHz to 10 kHz. Moderate gain. Maximum total gain 15 dBV @ 5 kHz with both Gain controls at 50%, or 24 dBV with Gain controls at 100%. Circuit suitable for 6/7-string guitar in standard tuning. [Not for 8-string guitar or bass.] For more gain, the value of the Gain 2 control can be increased, up to 10M for 43 dBV (making the circuit an overdrive). Do not go greater than 10M there, do not change the value of the Gain 1 control, and do not alter other components except during breadboard testing, if desired for obtaining a different response curve.