Marshall Jmp Lead 50W 1987 preset

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

The Marshall 1987 Super Lead 50W is one of the most iconic guitar amplifiers ever built. The two-EL34 power section reaches the sweet spot of output-stage saturation at volumes achievable on larger club stages, producing the singing, harmonically rich overdrive that defined British rock in the late 1960s and 1970s. Many players consider the 50W plexi even more tonally complex than its 100W counterpart, as the smaller power transformer sags more dramatically under heavy picking attack. This model's four-input, two-channel topology encouraged players to cross-patch channels for an early form of channel blending.

• Years produced: 1966–1981
• Made in: UK
• Wattage: 50W
• Channels: 2
• Preamp tubes: 3× ECC83 (12AX7)
• Power tubes: 2× EL34

Known for: Angus Young, Slash, Gary Moore.

Heard on: Back in Black — AC/DC (1980).

Tags: british, vintage, 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.