Roland JC-120 Jazz Chorus preset

Verified · 88/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The JC-120 Jazz Chorus is Roland’s solid-state 2x12 combo from 1975, with two power amps feeding the speakers in stereo. Channel 1 has high and low inputs, a bright switch, volume and treble/middle/bass, and is famously clean and loud. Channel 2 has the same controls plus a footswitchable distortion, spring reverb and Roland’s bucket-brigade (MN3007) stereo chorus and vibrato. It became a standard for clean tones in jazz, new wave and post-punk.

• Years produced: 1975–present
• Made in: Japan
• Wattage: 120W
• Channels: 2

Known for: Andy Summers, Johnny Marr, Adrian Belew, Billy Duffy.

Heard on: Elephant Talk — King Crimson (1981); She Sells Sanctuary — The Cult (1985); Receiver — Johnny Marr (2022).

Tags: japanese, solid-state, clean, high-wattage, 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.