Marshall 20W Bass 2019 - Main preset

Verified · 82/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Marshall 2019 is a 20-watt tremolo-equipped JMP-era combo, combining the classic Marshall preamp topology with a tube-driven tremolo circuit for modulation. These relatively compact Marshall tremolo models offered working musicians both the signature British crunch and rhythmic tremolo effect in a single unit, making them versatile for club and theatre work throughout the late 1960s and early 1970s. The tremolo circuit draws from the same era as the larger tremolo heads and shares their warm, oscillating character.

Tags: british, 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.