A Lowrey Royale SU500 / Palladium 630 organ (high end model) Lowrey Holiday Deluxe Model LSL (1961) has a built-in Leslie speaker. It was first sold in 1949 It was a successful competitor to the Hammond Solovox. This added electronic organ stops on 60 notes while keeping the piano functionality. Lowrey had earlier developed an attachment for a piano. It was called the Model S Spinet or Berkshire.
It was in 1955, the year he died, that Lowrey's full-sized electronic organ was first commercially successful. He was a Chicago-based industrialist and entrepreneur. The Lowrey organ is an electronic organ named for its developer, Frederick C.
