Leslie Speaker
Combined amplifier + rotating loudspeaker, invented by Donald Leslie (production from 1941) to give the Hammond organ the spatial richness of a pipe organ.
How it works
- Treble: rotating horn above a stationary compression driver.
- Bass: rotating drum/baffle beneath a stationary woofer.
- The moving sound sources create Doppler pitch shifts and tremolo — the most distinctive part of the effect is actually the speed transition, not either steady state.^[raw/articles/wikipedia-hammond-organ.md]
- Two speeds: chorale (slow) and tremolo (fast), toggled via the console's half-moon switch or a pedal.
Key models
| Model | Notes |
|---|---|
| 122 | Balanced signal, for console organs (B-3/C-3/A-100) — the classic pairing |
| 147 | Unbalanced signal, spinets (with adapter) |
| Pro-Line | Portable solid-state series, popular with gigging bands in the 1970s |
| Heritage | Modern reissues (Hammond-Suzuki), tube preamp, 122/147 switchable |
History notes
Hammond refused it 1940, "Leslie-proof" connectors were defeated, official support only came in 1966; first integrated Leslie in a Hammond was the T-200 (1968). Hammond bought the brand in 1980; Hammond-Suzuki owns it since 1992 and still builds 122 reissues plus a Leslie stomp-box simulator. Electronic imitators: Uni-Vibe, Neo Ventilator.^[raw/articles/wikipedia-leslie-speaker.md]
Related
- hammond-b3 — canonical partner
- vibrato-chorus — the other great Hammond "motion" effect (internal, scanner-based)