Gibson GA-20 - Normal preset

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

The Gibson GA-20 is a foundational mid-range combo amplifier from the 1950s GA series, producing 14 watts through a push-pull pair of 6V6 output tubes. Among the most characteristic Gibson amplifiers of the 1950s, the GA-20 delivers the warm, midrange-forward American clean tone that made Gibson amps the preferred tools of blues, country, and early rock and roll players. Two channels accommodate both a guitar and a microphone or second instrument, and the 6V6 output section breaks up naturally into a sweet, musical crunch when pushed.

Known for: Chuck Berry, B.B. King.

Tags: american, vintage, clean, crunch.

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.