RO 5-Stage RCA Tube Preamp PUBLIC

Richter Original 5-Stage Guitar Preamp Using RCA Circuits

Richter Original 5-stage real-tube guitar preamp using circuits from the 1965 RCA Receiving Tube Manual # RC-24, pages 544 and 545; "Low-Distortion Preamplifier" and "Bass and Treble Control Amplifier". Controls Include: Input Level, Bass, Mid-Center, Treble, Drive 1, Drive 2, and Volume. Intended for 6-string electric guitar. Not meant to provide much gain but rather to provide overdriven tube distortion like that of an American-made boutique guitar-amplifier. Both specified tube types were designed for use with single +12VDC power-supply for plates and heaters (originally a car battery). Note that the dual triode is reported to work like a 12AU7 except for the plate and heater voltages. [Do not substitute any other tube for the 12U7s, including 12AU7s, and there is no other tube number.] The tubes are available at The Tube Store. https://www.thetubestore.com . Experimental circuitry. No simulation. Frequency response and overall gain must be determined during breadboard testing. Power-supply not shown. Requires a regulated single-polarity DC supply providing +12VDC @ >= 1A of current. Example: 12V DC 1000 mA Regulated Switching Power Adapter, Product ID: 798. $8.95 each. From the AdaFruit website. https://www.adafruit.com