Marshall JMP Specialist 2046 preset

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

The Specialist 2046 is a 25-watt Marshall from the early 1970s with an unusual power section: two EL34s stacked in series (totem-pole push-pull) driven by a cathodyne phase inverter into a 16-ohm output. Two inputs feed an ECC83 stage, Volume and a simple treble and bass network. An ECL86 drives and recovers the spring reverb with its own level, and a second ECC83 phase-shift oscillator with speed and depth adds footswitchable tremolo.

• Made in: UK
• Wattage: 25W
• Channels: 1
• Preamp tubes: 2× ECC83, 1× ECL86
• Power tubes: 2× EL34

Tags: british, vintage, reverb, el34, mid-wattage.

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.