Ampeg Gemini II G-15 - Channel 1 preset

Verified · 87/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg Gemini II G-15 is a two-channel guitar combo with a 15-inch speaker. Each channel has volume, bass, treble and an Ultra Hi switch, with 6CG7-driven reverb and a footswitchable 12AX7 tremolo. A 7199 phase inverter drives a pair of 6L6GCs for about 30 watts.

• Made in: USA
• Wattage: 30W
• Channels: 2
• Preamp tubes: 3× 12AX7, 1× 7199, 1× 6CG7
• Power tubes: 2× 6L6GC

Known for: Peter Buck, Igor Haefeli.

Heard on: Radio Free Europe — R.E.M. (1983); Doing the Right Thing — Daughter (2016).

Tags: american, vintage, 6l6, reverb, tremolo, two-channel, mid-wattage.

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.