Piano EffectLeslie
The rotating speaker of the Hammond organ: tremolo, vibrato and Doppler at once. Slow (chorale) or fast (tremolo).
How to recognise it by ear
- The organ "spins": volume and pitch undulate together, with a beating that stands out in the highs.
- The giveaway is the speed change: the organist switches from slow to fast and the rotor ramps up over a couple of seconds.
- In gospel and rock it usually runs fast and overdriven; in jazz and boleros, slow.
Typical settings
Slow ≈ 0.7–0.9 Hz; fast ≈ 6–7 Hz. Doppler from 8 to 20 cents.
What Piano Effect measures
The rotor rate, whether it is slow or fast, its depth and the Doppler in cents. Leslie apps simulate it; this one measures it.
Android: get it on Google Play
Library sounds that use it
- Cumbia organslow rotor (≈ 0.8 Hz)
- Norteño keyboardslow rotor (≈ 0.8 Hz)
- Bolero organslow rotor (≈ 0.8 Hz)
- Jazz organ (B3)slow rotor (≈ 0.8 Hz)
- Gospel organfast rotor (≈ 6.7 Hz)
- Rock organfast rotor (≈ 6.7 Hz)
Frequently asked questions
What is a Leslie speaker?
The rotating speaker of the Hammond organ: tremolo, vibrato and Doppler at once. Slow (chorale) or fast (tremolo). The giveaway is the speed change: the organist switches from slow to fast and the rotor ramps up over a couple of seconds.
How can I tell if a song uses Leslie?
The organ "spins": volume and pitch undulate together, with a beating that stands out in the highs. The giveaway is the speed change: the organist switches from slow to fast and the rotor ramps up over a couple of seconds. To be sure, scan it with Piano Effect: it tells you whether it is there and with which values.
What Leslie settings are typical?
Slow ≈ 0.7–0.9 Hz; fast ≈ 6–7 Hz. Doppler from 8 to 20 cents.