Marshall 8004 Power Amp preset

Verified · 90/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The 8004 is a 2x40-watt stereo solid-state rack power amp from 1991, built to follow Marshall's Valvestate-era rack preamps. Left and Right inputs, with the right mono-linkable, each drive a TDA1514A power IC into its own 40 W, 8-ohm output. A Valvestate/Linear switch changes the output stage's feedback and response, and BDV64/BDV65 transistors regulate the supply rails. It has no preamp or tone controls.

• Made in: UK
• Wattage: 80W
• Channels: 1

Tags: british, solid-state, power-amp, stereo.

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.