The Leslie Speaker- What a fascinating piece of vintage technology

[astro]

I never even knew this thing existed.

It’s fascinating! This tech is 70 years old.

The Leslie Speaker wiki

UNEARTHING THE MYSTERIES OF THE LESLIE CABINET

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 KFI near Los Angeles, a contract was made to install another prototype in the station’s studios, where Mitchell would be the only organist authorized to use it. Mitchell was so impressed that he even tried to patent the speaker, but discovered that he couldn’t. Soon afterwards, Mitchell became an organist with the Mutual Broadcasting System, and played a Hammond with the Leslie on its shows. The national exposure was swift and sure. Organists, professional and amateur alike, wanted to have “that sound”. Jazz organist Jimmy Smith helped to popularize “that sound” among rock-n-roll musicians in the late 1950s and early 1960s. The Leslie of that time was over sixty inches tall (about the size of a modern refrigerator), and was named the 30A. Don Leslie made a whole series based on the 30A, called “Tall Boys” (31 series). In the 1950s, Leslie introduced the 21H for use in homes, concert hall venues and smaller radio sound stages.

[astro]

Here’s a youtube video on how it works.

[Folacin]

Childhood memory - we had an electronic organ, and one of the switches was for “Leslie effect” - know I know what it was supposed to do.