Single-Battery Preamp 1 PUBLIC

2-Stage guitar preamp powered by a single 9-volt battery,

2-stage guitar preamp powered by a single 9V battery. Controls Include: Input Attenuation enable switch (Attenuate or Direct), Attenuation control, Input Gain, Drive, Output Gain, and Volume. No tone controls. Frequency Range 30 Hz to 20 kHz. Maximum Gain +20.4 dBV @ 400 Hz with all controls at 50%, or twice that with controls at 100%. Suitable for 6/7/8-string guitar or 4/5/6-string bass. As is, this is a medium-gain circuit for signal stabilization and boosting. For gain sufficient for standard clean overdrive, Gain pot values can be increased to 250k. For high-gain overdrive, go to 500k. The circuit 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 wholly experimental. Breadboard test it before committing to a soldered build. And house in a grouned metal enclosure.