RO Tube-Sovereign Preamp PUBLIC

Richter Original "Tube-Sovereign" 5-Stage Guitar Preamp

Richter Original "Tube-Sovereign" 5-stage guitar preamp, with shunt-diode fuzz and 2-band Baxandall-style tone. Controls Include: Input Level, Fuzz enable switch, Fuzz symmetry switches, Fuzz Enable, Drive, Intensity, Bass, Mid-Center, Treble, and Volume. All tubes were designed to be operated using a single +12VDC supply-voltage (originally from a car batter) on plates AND heaters. All tubes are available online as NOS tubes at The Tube Store. https://www.thetubestore.com . Experimental circuitry. Untested design. No simulation. Frequency response and overall gain must be determined during breadboard testing. The 12U7 was designed to be a 12V version of the 12AU7, and should sound like it (do not substitute any other tube, including 12AU7). The Input and Gain Stages should also sound like the front-end of a Fender "Champ" using a 12AU7 instead of a 12AX7. Q3 and Q4 together form a clean boost that should sound like the front-end of a Supro model 1606 "Super" amplifier, though using the 12AK8 instead of a 12AX7 with a 6V6. Q5 is used in an accurate version of the original Baxandall tone-control but using a 12DZ6 pentode instead of the originally-specified SP61. This project is therefore intended overall to sound like a custom American-made boutique all-tube preamp but with a solid-state power-supply. Power-supply not shown. Example Supply: 12V DC 1000 mA Regulated Switching Power Adapter, Product IDL 798. $8.95 each. From AdaFruit website. https://www.adafruit.com