Rob Robinette RR2104 Master Volume Micro EF80 preset

Verified · 85/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The RR2104 Micro EF80 (drawn as RR800M-EF80) puts Rob Robinette’s JCM800 2204 circuit into a Princeton Reverb chassis. Three 12AX7s handle the preamp, with high and low inputs, preamp volume, a cold clipper, a third gain stage and cathode follower into the treble/bass/mid stack, then master volume, presence and a long-tail inverter. A push-pull pair of EF80 pentodes makes about 1 watt from a solid-state rectifier and choke supply.

• Made in: USA
• Wattage: 1W
• Channels: 1
• Preamp tubes: 3× 12AX7
• Power tubes: 2× EF80

Tags: american, diy, crunch, high-gain, low-wattage.

Schematic-derived preset files for 16 Fractal and Line 6 modelers: Axe-Fx II/XL/XL+, Axe-Fx III, FM3, FM9, and the full Helix family (Floor, LT, Rack, HX Stomp, HX Stomp XL, Native).

Gridleak extracts amp parameters from original circuit schematics using AI vision — component values, gain staging, tone stack topology, tube types — then generates native preset files for every supported modeler. Every extraction is scored 0–100 and the score is published.