Interface
Unlike most popular music amplifiers and equipment, Leslie Speakers use an amphenol connector to interface directly to an organ. Older models that used tube power amps used a variety of 6-pin connectors, while later models used a 9-pin connector. In all cases, the mains power, audio and control signals were all carried on the connector, and the design of the pin layouts varied between organs and speakers. Care must be taken when attempting to service them, as an incorrectly or poorly wired cable can cause permanent damage to the organ and / or speaker, or result in electrocution.
A separate device known as the "Combo Preamp" is necessary to connect a vintage Leslie to another instrument such as a guitar. The Combo Preamp combines a separate AC input and line level input onto a single amphenol connector. Modern products such as the Trek II UC-1A allow any instrument with a phone jack connection to use a variety of Leslie speakers.
Modern Leslie speakers have an 11-pin interface that is safer to service, as the mains power is carried separately using a standard IEC mains connector.
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