Sequential is an American synthesizer company founded in 1974 as Sequential Circuits by Dave Smith. In 1978, Sequential released the Prophet-5, the first programmable polyphonic synthesizer, used by artists including Michael Jackson, Madonna, and John Carpenter. Sequential was also pivotal to the development of MIDI in 1982, which synchronizes electronic instruments by different manufacturers. Smith continued to develop instruments through a new company, Dave Smith Instruments. In 1987, Sequential went out of business. Smith blamed the decision to move to computer audio in 1985: “We were too small and under-capitalized, and we were a few years too early in the market … It drained our resources, so by the time we pulled back to professional instruments, it was too late.” Sequential was purchased by Yamaha, who shut it down in 1989. Smith moved to Korg, where he worked mainly on the Wavestation synthesizer. After several years working on software synthesis, in 2002 Smith opened a new company, Dave Smith Instruments (DSI), to build new hardware. Its first product was the Evolver synthesizer in 2002. In 2008, DSI launched the Prophet ’08, conceived as an affordable analog eight-voice synthesizer. In January 2015, Yamaha returned the Sequential and Prophet brands to Smith in a goodwill gesture. This was at the encouragement of Roland founder Ikutaro Kakehashi, who had worked with Smith to create MIDI. Kakehashi said: “I feel that it?s important to get rid of unnecessary conflict among electronic musical instrument companies. That is exactly the spirit of MIDI. For this reason, I personally recommended that the President of Yamaha, Mr. Nakata, return the rights to the Sequential name to Dave Smith.”[15] In 2015, Smith announced the Prophet-6, described as a spiritual successor to the Prophet-5. In May 2018, Sequential announced the Prophet-X, featuring both sample playback and digitally controlled oscillators. On August 31, 2018, the 40th anniversary of the Prophet-5, Dave Smith Instruments rebranded as Sequential.