What tubes does the Gibson Ga83S Preamp use?

The Gibson Ga83S Preamp uses 4× 12AX7 preamp tubes and 4× 6L6 power tubes.

When was the Gibson Ga83S Preamp produced?

The Gibson Ga83S Preamp was produced 1959–1963.

Gibson Ga83S Preamp preset

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

This schematic covers the preamplifier section of the Gibson GA-83S Stereo, documenting the dual-channel preamp topology that feeds the amp's two independent power stages. The preamp uses multiple 12AX7 stages to develop the signal for stereo output, with tone controls and channel switching handled before the signal splits to the independent power amplifiers. Understanding this preamp stage is key to appreciating how Gibson achieved true stereo sound in a guitar combo in the late 1950s.

Years produced: 1959–1963
Made in: USA
Wattage: 40W
Channels: 2
Preamp tubes: 4× 12AX7
Power tubes: 4× 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.