Electronic music pioneer Don Lewis has died. Pitchfork reports that the composer and musician, who created an instrument called the Live Electronic Orchestra (LEO), passed away on Sunday (November 6). He was 81 years old.

Lewis grew up in Dayton, Ohio and developed an interest in music as a child after watching an organist perform at his church. He studied electronics engineering student at the former Tuskegee Institute, where he also joined the Tuskegee Chorus and played music at rallies for Martin Luther King Jr. In 1961, he enlisted in the Air Force and served as a Nuclear Weapons Specialist for four years in Roswell, New Mexico. He then relocated to Denver, Colorado, where he worked as an engineering technician, before quitting his job to become a full-time musician and moving to Los Angeles.

Lewis designed LEO, a synthesizer system linking multiple synths together that predated the MIDI controller by ten years, in 1974 and completed it in 1977. He also worked with Roland founder Ikutarô Kakehashi on rhythm units such as the FR-7L, CR-68, and CR-78, and contributed to the making of the Yamaha DX7.

Lewis collaborated with a number of notable musicians and producers, including Quincy Jones, Sergio Mendez, and Michael Jackson. He also opened for the Beach Boys on their 1974 tour and performed at the 1975 and 1976 Newport Jazz Festival.

A feature-length documentary chronicling his life, Ned Augustenborg’s The Ballad of Don Lewis: The Untold Story of a Synthesizer Pioneer, was released in 2020. The film will make its US broadcast debut on PBS in February 2023 as Don Lewis and the Live Electric Orchestra.