What tubes does the Gibson GA Custom - Instrument use?

The Gibson GA Custom - Instrument uses 3× 6SJ7, 2× 6J5, 2× 6SQ7 preamp tubes and 2× 6L6 power tubes.

When was the Gibson GA Custom - Instrument produced?

The Gibson GA Custom - Instrument was produced 1949–1953.

Gibson GA Custom - Instrument preset

Verified · 84/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The GA Custom is Gibson's GA-CB Custom Built, the costly flagship of its late-1940s line. A Microphone input on one 6SJ7 and three instrument inputs on two more share bass and treble controls, and two 6SQ7s run a tremolo with intensity, frequency and a footswitch. Two 6J5s form a paraphase inverter for a push-pull pair of 6L6s on a 5T4 rectifier, driving a coaxial 15-inch speaker through a dividing network.

Years produced: 1949–1953
Made in: USA
Channels: 2
Preamp tubes: 3× 6SJ7, 2× 6J5, 2× 6SQ7
Power tubes: 2× 6L6

Tags: american, vintage, clean, 6l6.

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.