What tubes does the Leslie 147 use?

The Leslie 147 uses 1× 12AU7 preamp tubes and 2× 6550 power tubes.

Who famously used the Leslie 147?

George Harrison are among the notable players associated with the Leslie 147.

What recordings feature the Leslie 147?

Something by The Beatles (1969).

Leslie 147 preset

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

The power amplifier for the Leslie 147 rotating-speaker cabinet, which runs with Hammond organs; this is not a guitar amp. A 12AU7 paraphase driver feeds two 6550s at about 40 watts, with an OC3 voltage regulator, a console-load switch and a tremolo relay that switches rotor speed. Guitarists often use these amps with a Leslie cabinet.

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

Known for: George Harrison.

Heard on: Something — The Beatles (1969).

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.