RO Experimental 12V-Champ Preamp PUBLIC

Richter Original Experimental 12V-Champ Preamp for Guitar

Richter Original experimental 12-volt preamp circuit based on the Fender 5E1 Champ guitar amplifier, highly-modified to work using a +12VDC power-supply. Both tubes are space-charge types designed for +12V plate AND heater supply-voltages. Controls Include: Drive, Feedback enable switch, Feedback level, Feedback phase switch, Tone, and Volume. No output transformer and no speaker. Use circuit only as a preamp (but will drive headphones). The input can be overdriven by a boost or overdrive stomp-box, and the pentode can be overdriven by the second triode, depending on the setting of the Drive control. Overall Frequency Range 20 Hz to 16 kHz with all controls at 50%. Overall Gain = +20 dBV (Vo/Vi = 10). Power-supply not shown. Requires a regulated single-polarity DC supply providing +12VDC @ >= 500 mA. Regulated wall-wart allowed. Example: Bel SWM6-12-VH-P5. DigiKey # 179-SWM6-12-NH-P5-ND. $15.05 each. Available at DigiKey. https://www.digikey.com . Recommend rack-mount implementation with vibration-damping mounts. And use pads on the tubes to help mitigate vibrational noise.