Bobby says that Hammond organs and Leslie speakers are considered inseparable on his blog post at bobbyowsinski.blogspot.com. However, the Hammond organ was manufactured years before the Leslie speaker was created. Don J. Leslie created these wonderful speakers and tried to sell the idea to the Hammond Organ Company, but was rejected. Don Leslie then went into business for himself, founding the company Electromusic, to make the Vibratone. The Hammond Organ Company did not acknowledge the speakers’ existence, despite the pairing. The speaker was popularly called the Leslie Vibratone until people simply shortened this to the ‘Leslie’, as we know today.
If you want to know the story behind Hammond organs and Leslie speakers then read the full article here: