Gibson GA-85 - Channel I preset

Close · 72/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The Gibson GA-85 is a large-format professional combo from the mid-1960s, delivering around 50 watts through four 6L6 output tubes in a multi-speaker cabinet. It is among the most powerful combos in the GA lineup and was designed for large venue stage work during an era when PA reinforcement was still minimal. Two channels, substantial clean headroom, and a warm American tone character define this amp. The GA-85 represents Gibson's competition with Fender's top-tier Twin and Super Reverb in the mid-1960s market.

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.