Leslie 122 / 122R preset

Verified · 85/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The amplifier for the Leslie 122 rotating-speaker cabinet, which runs with Hammond organs; this is not a guitar amp. The main amp uses 12AU7s to drive two 6550s at about 40 watts, and the 122R version adds a separate reverb amplifier with a pair of 7189s. Guitarists often rehouse these amps or run them through a Leslie cabinet.

• Made in: USA
• Wattage: 40W
• Channels: 1
• Preamp tubes: 2× 12AU7
• Power tubes: 2× 6550

Tags: american, vintage, 6550, power-amp.

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.