Marshall Major 200W preset

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

The Marshall Major 200W is the standard production version of Marshall's flagship 200-watt head, representing the peak of the company's early ambition to produce the loudest possible amplification for stadium-scale touring. Its quad KT88 output section generates prodigious clean headroom while maintaining the basic plexi circuit topology, and its large output and power transformers contribute to an unusually stable, authoritative response even under heavy playing. The Major was produced in relatively small numbers compared to the 50W and 100W lines, and surviving examples are prized by collectors and tone historians.

Known for: Ritchie Blackmore, Pete Townshend.

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.