What tubes does the Gibson GA-40T Crestline - Channel I use?

The Gibson GA-40T Crestline - Channel I uses 3× 12AX7 preamp tubes and 2× 6L6 power tubes.

When was the Gibson GA-40T Crestline - Channel I produced?

The Gibson GA-40T Crestline - Channel I was produced 1962–1967.

Gibson GA-40T Crestline - Channel I preset

Verified · 80/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The GA-40T Crestline added tremolo to the GA-40 platform, giving players a hypnotic amplitude modulation effect alongside the amp's robust 6L6 clean tones. The Crestline name was part of Gibson's mid-1960s rebranding of their amplifier lineup with updated cosmetics. The tremolo circuit is tube-driven and produces the slow, warm throb characteristic of American amps of the period. With two channels and solid clean headroom, the GA-40T Crestline is a versatile vintage combo well suited to clean and light crunch tones.

Years produced: 1962–1967
Made in: USA
Wattage: 25W
Channels: 2
Preamp tubes: 3× 12AX7
Power tubes: 2× 6L6

Tags: american, clean, vintage.

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.