Mesa Boogie Mark IIC+ preset

Verified · 86/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Mark IIC+ is the final Mark II revision and one of the most prized Mesa/Boogies. Its cascaded lead path through LDR-switched stages, Mark tone stack and 5-band graphic EQ produce a tight, singing high-gain tone. Metallica used IIC+ heads on Master of Puppets, and John Petrucci's signature JP-2C recreates the circuit.

• Years produced: 1984–1985
• Made in: USA
• Wattage: 100W
• Channels: 2
• Preamp tubes: 5× 12AX7
• Power tubes: 4× 6L6

Known for: James Hetfield, Kirk Hammett, John Petrucci, Prince, Steve Lukather, Michael Landau.

Heard on: Master of Puppets — Metallica (1986); Enter Sandman — Metallica (1991); A Nightmare to Remember — Dream Theater (2009).

Tags: american, high-gain, metal, 6l6, two-channel.

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.