What tubes does the Marshall 1964 Jmp Lead And Bass use?

The Marshall 1964 Jmp Lead And Bass uses 4× ECC83 preamp tubes and 4× EL34 power tubes.

When was the Marshall 1964 Jmp Lead And Bass produced?

The Marshall 1964 Jmp Lead And Bass was produced 1963–1967.

Marshall 1964 Jmp Lead And Bass preset

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

The Marshall JMP 1964 Lead & Bass was a dual-channel 100W head produced in the early JMP era, providing independent inputs for lead guitar and bass guitar from a shared power section. It offered early Marshall players the flexibility to use one amp for both instruments.

Years produced: 1963–1967
Made in: UK
Wattage: 100W
Channels: 2
Preamp tubes: 4× ECC83
Power tubes: 4× EL34

Tags: british, vintage, early-jmp.

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.