Leslie speaker

The Leslie speaker is a specially constructed loudspeaker used to create special audio effects. Named after its inventor, Don Leslie, it is particularly associated with the Hammond organ. Separate Leslie speakers were a "must have" accessory for all Hammond owners, particularly after its characteristic sound was popularised by such acts as Procul Harum on A Whiter Shade of Pale or the Spencer Davis Group on Gimme Some Loving. Although the Leslie speaker and the Hammond organ are spoken of as one organized musical system, Hammond never owned or manufactured any speakers or parts for the Leslie Corporation, much less advertise for it. Hammond refused to package any Leslie speakers with its organ sales using, instead, its own speakers which produced virtually no "Leslie like" spatial effects. Hammond did begrudgingly repair Leslie units,only when asked, to cement the bond of loyalty between itself and its customer base.

Don Leslie, at the outset, was refused hire by the Hammond Organ Company, but did work for the local electric company, in a contract with Hammond, to replace the old fifty cycle rotor tone generators with the new sixty cycle units- in customers' homes. Its first name, in 1941 was the "Vibratone", (used later by Fender Guitar Company for a rotating speaker-like effects unit and speaker system and the name "Leslie" after Leslie had sold his company to CBS in 1965, which had also acquired Fender). From 1941, when the first units were produced it carried several names like "Brittain Speakers", "Hollywood Speakers" and "Crawford Speakers", then finally returning in 1946 to the name "Leslie Vibratone". Who bought the first Leslie is still a mystery. After seventeen years from rejecting him, Leslie offered to sell the company to Hammond. After thirty days he heard no word from Hammond. Don Leslie said: "After seventeen years, the thirty day period is up. Too late".

Leslie never advertised his speakers. After demonstrating a prototype (a rotating baffle in a hole in a small closet with a big speaker in the closet near Leslie's home organ) with Bob Mitchell, an organist with radio station KSI near Los Angeles, CA, a contract was made to install another prototype in the studios in which Don Mitchell would be the only authorized organist to use it. Mitchell was so impressed he even tried to patent it, but found out he couldn't. Mitchell soon became an organist with the Mutual Broadcasting System and used the Leslie with a Hammond on its shows. The national exposure was swift and sure. Almost immediately organists, professional and amateur alike, wanted to have "That Sound". The Leslie of that time was over sixty inches tall,about the size of a modern refrigerator, and was named the A30. Don Leslie Made a whole series based on the A30, called "Tall Boys". In the 1950s Leslie introduced the 21H. It could fit into homes as well as concert hall venues and smaller radio sound stages. Since the A30 Leslie has had all it can do to fill its orders.

Happily, Leslie parts are quite available from a number of sources. There are also websites where can get plans and photgraphic examples for constructing a Leslie speaker, but with much improved electronics and speakers. On the web one can see a 500W high performance Leslie.

As a note, the first model to have two speeds, the model 125, was introduced in 1963. All preceding models were one speed only. Leslie produced two editions of each model. One for Hammonds (H) and one for Wurlitzer (W). Many organists still use combinations of these editions. Leslie also made an edition for Conn, the 50C, the first Leslie to have two discrete channels.

The smallest Leslie-to-date is the Leslie Model 16, made in 1970. It has a Fender-like speaker body and a rotating foam dispersion block. It was built for rough club touring, was portable and Had "Leslie" on the front. It was also released later as Fender/CBS's "Vibratone". Stevie Ray Vaughn loved his and it can be heard on the album, STEVIE RAY VAUGHN AND DOUBLE TROUBLE LIVE AT THE EL MOCAMBO. Also heard on Eric Clapton's "Badge" and Jimi Hendrix' "Little Wing". With more demand and supplies decreasing, its availability is becoming rare.

The Leslie speaker consists of two driver units - a treble unit with horns, and a bass unit. The key feature is that the horns of the treble unit, (the treble unit has only one horn in fact but it looks like two because a dummy horn is used to counter-balance the horn that works) and a sound baffle for the bass unit, are rapidly rotated using electric motors to create 'Doppler effect-based' vibrato, tremolo and chorus effects. It can be switched between its two speeds, fast/slow and its the transition between the two that produces the most characteristic effects. The resulting sound is instantly identifiable as that of the Hammond organ, frequently heard on psychedelic and rock music of the 1960s and 1970s. Unlike a high fidelity loudspeaker, the Leslie is specifically designed, via reproduction of this Doppler effect, to alter or modify sound, not reproduce it, and so faithful reproduction has never been part of its appeal. Much of the sound is owed to the fact that the system is at least partially enclosed, but with linear louvres along the sides and front so that the unit can vent the sound from within the box after the sound has bounced around inside and mellowed it.This produces the very rich and unique and characteristic 'toney' sound. The Leslie may thus be thought of as an electro-mechanical sonic effects machine. Many rock and roll organists have typically turned the box around to expose the horn's rotation for a visual effect, and in hopes of projecting a more powerful sound from both speakers. One can see such a reversed placement in The Band's movie, THE LAST WALTZ and in WOODSTOCK: THE MOVIE.

While normally used with the Hammond, because it is a separate unit, any musical source, such as an electric guitar, can be played back through it, creating a wide range of surprising and dramatic effects. The classic Leslie is still made and sold to this day, though in modern times similar effects can be obtained digitally. The first successfully recorded example of Leslie emulation came from Keith Emerson's Yamaha GX-1 synthesizer on ELP's "Pirates". The digital emulators, however, have thus far fallen short of completely achieving the unique Leslie magic.


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