Single-Battery Preamp 2 PUBLIC

Guitar preamp powered by a single 9-volt battery, with two Gain stages, and 2-band tone.

Guitar preamp powered by a single 9V battery. Two clean gain stages and 2-band tone. Controls Include: Input Attenuation enable switch (Attenuate or Direct), Attenuation control, Gain 1 and Gain 2, Drive, Bass, Treble, and Volume. Range is from 50 Hz to 20 kHz. Suitable for 6/7-string guitar or 4-string bass (not recommended for 8-string guitar or 5/6-string bass). Maximum gain = +12.3 dBV @ 800 Hz with all controls at 50%, and twice that with controls at 100%. Circuit will work for tone-shaping, gives a modest boost, and emphasizes the mids. It is meant for stomp-box projects, but the battery can be replaced by a regulated single-polarity DC supply providing +9VDC or +12VDC or +15VDC at >= 20 mA of current. And though simulator verified, treat the circuit as experimental. Breadboard test before soldering.