Bogen GA20 - Instrument preset

Verified · 88/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Bogen GA20 is a 20-watt tube instrument amplifier from this American commercial audio specialist, designed to serve both PA and instrument amplification duties in small venues and institutional settings. Bogen's GA series represented the company's dedicated instrument amplifier offerings, built with the same quality standards as their commercial PA line. Vintage audio enthusiasts and guitarists have long appreciated these amps for their warm, honest tube character.

Tags: american, 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.