Gibson GA-20RVT Minuteman - Reverb preset

Verified · 92/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The GA-20RVT Minuteman is a 1960s Gibson combo with Normal and Reverb channels, two inputs each, and loudness, bass and treble controls on each channel. The Reverb channel has a 12AU7-driven spring reverb with a level control, and a photocell tremolo has depth and frequency, both footswitchable. A 12AU7 drives a cathode-biased push-pull pair of 6BQ5 (EL84) tubes through a driver transformer, on a solid-state rectifier, into a 12-inch speaker.

• Made in: USA
• Channels: 2
• Preamp tubes: 3× 6EU7, 2× 12AU7
• Power tubes: 2× 6BQ5

Tags: american, vintage, clean, reverb, tremolo, two-channel.

Schematic-derived preset files for the Neural DSP Quad Cortex and 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.