Leslie speaker
loudspeaker known for its rotation effect and association with the Hammond organ
The Leslie speaker is a combined amplifier and loudspeaker that modifies the sound of an electric musical instrument by rotating a baffle chamber (drum) in front of the loudspeaker. A similar effect is provided by a rotating system of horns in front of the treble driver. It is most commonly associated with the electric Hammond organ, though it was later used for the electric guitar and other instruments. A typical Leslie speaker contains an amplifier, a treble horn and a bass speaker—though specific components depend upon the model. Some models have two speed settings, known as chorale and tremolo.
The speaker is named after its inventor, Donald Leslie, who began working in the late 1930s to get a speaker for a Hammond organ that better emulated a pipe or theatre organ, and discovered that baffles rotating along the axis of the speaker cone gave the best effect. Hammond was not interested in marketing or selling the speakers, so Leslie sold them himself as an add-on, targeting other organs as well as Hammond, beginning in 1941. The sound of the organ being played through his speaker received national radio exposure across the US, and it became a commercial and critical success, becoming popular with jazz organists. In 1965, Leslie sold his business to CBS who, in 1980, sold it to Hammond. Suzuki Musical Instrument Corporation subsequently acquired the Hammond and Leslie brands.
“Leslie speaker” enters the record as loudspeaker known for its rotation effect and association with the Hammond organ. Crown Archives preserves that source wording while asking what Leslie, speaker and loudspeaker can confirm, complicate or overturn.
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Contemporary correspondence, administrative files and participant testimony can test how later narratives organized the event or institution. The source revision retrieved here is dated Sep 10, 2026. The linked authority identifier is Q1820781. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1941, 1965 and 1980.
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This entry incorporates text from “Leslie speaker” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.