Marshall Jtm100 Lead Trem 100W 1959T preset

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

The Marshall JTM100 Lead Tremolo (sometimes catalogued as an early 1959T variant) is one of the rarest and earliest Marshall 100W heads, produced during the transitional period between the original JTM45 and the standardised JMP range. Using KT66 output valves like the original JTM45 rather than the EL34s that would become standard, it delivers a rounded, slightly warmer character than the later plexi Super Lead, with a touch of compression that KT66s are known for. The addition of a tremolo circuit on a 100W head was unusual and makes surviving examples exceptional collector pieces.

Tags: british, crunch, high-gain.

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.