[3] In 1941, Leslie founded Electro Music in Pasadena, California to manufacture and market the speaker, which he named the Vibratone 30A.
[1] Hammond, opposed to devices designed to alter the sound of their organs, went to great lengths to disassociate their product with Leslie's, including changing speaker connectors on newer models and forbidding Hammond organ merchants to sell Leslie speakers.
Even so, Leslie's speaker and the unique effect it produced became widely used with Hammond and various other brands of organs and other keyboards.
Its use extended beyond theaters and churches to influence jazz, psychedelic, rock, blues, gospel, and pop music, with even guitarists and vocalists capitalizing on its effect.
In addition to music, his hobbies included tennis, model railroads, and flying private aircraft in the US, Canada, and Mexico.