Music Man GP-3A preset

Verified · 86/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The GP-3A is a revision of the Music Man GP-3, built in 65 W and 100 W versions. High and low inputs feed an op-amp preamp with a bright switch, treble, bass and midrange and a Deep switch, then a dual-gang Gain control and transistor soft limiter ahead of the Volume. Spring reverb and a four-stage optical phaser with speed and intensity are footswitchable, and transistor drivers cathode-drive a pair of 6L6GC output valves.

• Made in: USA
• Wattage: 65W
• Channels: 1
• Power tubes: 2× 6L6GC

Tags: american, vintage, hybrid, clean, reverb, el34.

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.