Sequential Circuits Inc.

Sequential Circuits, Inc. was founded in 1974 in San Jose, California by American engineer and musician, Dave Smith (born 1950 in San Francisco, California), along with the help of John Bowen and Barb Smith. Smith earned degrees in computer science and electrical engineering from the University of California at Berkeley, though his interest in synthesizers began in 1972 when he acquired his first Minimoog. Sequential’s first products were a 16-step analog sequencer, known as the Model 600 Analog Sequencer, developed in 1974, a 16-step and 16-bank digital sequencer, known as the Model 800 Digital Sequencer, developed in 1975, and a sound storage unit capable of holding 64 programs, known as the Model 700 Programmer, developed in 1976. Design on the iconic Prophet 5, Sequential’s first real foray into the synthesizer market, began in 1977. In order to salvage the company’s declining sales, Smith contacted Dave Rossum and Scott Wedge of E-mu Systems, Inc. in the summer of 1977 to confer on new product ideas. The general consensus was that the market desired powerful analog synthesizers that were programmable, polyphonic, and, most importantly, affordable. E-mu had already developed the technology to implement digital scanning polyphonic keyboards and microprocessor-based SSM (Solid State Music) chip analog voice cards, however they were not financially equipped to take the risk on the mass production of a new and experimental product. As such, they agreed to license both the voice card and digital scanning keyboard technology to Sequential, with Smith overseeing the implementation of programmability and the interface, and Rossum handling the instrument’s operating system and analog circuitry. Following six months of co-development, the first prototype model of the Prophet 5 was revealed at the NAMM trade show in January of 1978. The Prophet 5 was a groundbreaking innovation in its being the first analog synthesizer to employ microprocessors for both polyphony and programmability. The Prophet 10 followed shortly after in 1980, and was essentially two Prophet 5s housed within a single enclosure. As such, it offered ten-voice polyphony across its two manuals, but extended beyond the Prophet 5 design to also feature an on board sequencer that was designed several years earlier. The Prophet 10 suffered considerable instability and overheating issues, and did not attain any significant level of commercial success. Another sequencer, known as the Poly-Sequencer, followed in 1980, and the Pro One, Sequential’s highly successful monophonic synthesizer, emerged in 1981. The Pro One featured a single dual-oscillator voice from the Prophet 5 design, but also incorporated an on board sequencer and arpeggiator.

Smith’s next major contribution came in late 1981, when he presented a paper at the Audio Engineering Society’s annual meeting theorizing the creation of a standard protocol that would allow various electronic instruments to communicate with one another. With the help of synthesizer designers Tom Oberheim of Oberheim Electronics, Ikutaro Kakehashi of Roland, and representatives from Korg and Kawai, the Musical Instrument Digital Interface – which was in fact coined by Smith and more commonly referred to as MIDI – was consecrated at NAMM in 1983 with a Roland Jupiter 6 and a Sequential Circuits Prophet 600 making the first successful connection. The Prophet 600, the first MIDI-equipped synthesizer, was revealed in 1982 along with the Pro-FX, a programmable multi-effects unit that included modules for phasing, distortion, EQ, reverb, flange, chorus, and delay. The Prophet T8, Sequential’s most sophisticated instrument, was released in 1983. The T8 featured eight-voice polyphony, and a 76-note weighted keyboard with velocity sensitivity and aftertouch. The Drumtraks, the first MIDI-equipped, sample-based drum machine, followed in 1983, along with the Six-Trak, the first MIDI-equipped, multi-timbral synthesizer capable of interfacing with a Commodore 64 computer, in 1984 and the Prophet 2000, a 12-bit sampling keyboard, in 1985. In 1986, Sequential introduced another groundbreaking innovation, the Prophet VS. The Prophet VS employed vector synthesis, a digital form that was relatively unheard of at the time. It also featured four digital oscillators per voice and an astounding 127 different waveforms for the user to choose from. Additionally, an onboard joystick allowed the user to mix or crossfade, so to speak, between various waveforms. Still to this day, the Prophet VS is revered for its unique and complex textures. Two final products, the Studio 440, an integrated music production system, and the Prophet 3000, a highly sophisticated rack mount sampler, were released in 1986 and 1987. Sequential, along with many other companies of the era, could not maintain their position in a highly competitive market that had become increasingly more sophisticated yet accessible with the introduction of the major Japanese manufacturers of the early 1980s, and, in 1987, Sequential ceased operations. Its name, assets, and research and development efforts were acquired by the Yamaha Corporation of Japan. Following this, Smith spent a few years consulting for the research and development divisions of both Yamaha and Korg, helping to design the latter’s successful Wavestation series of synthesizers, which employed a similar vector synthesis scheme to that used in the Prophet VS.

In 2002, Smith founded his new synthesizer manufacturing company, Dave Smith Instruments (DSI), currently based in the North Beach neighbourhood of San Francisco, California. Notable DSI products include the recent Prophet 6, the Pro 2 monophonic hybrid synthesizer, the Tempest analog drum machine that was co-designed with electronic instrument builder Roger Linn, the Prophet 12 hybrid synthesizer, the Prophet ’08 analog synthesizer, the Mopho monophonic synthesizer, and the Evolver monophonic module. Smith has received numerous honours and awards for his contributions, including a Technical Grammy he received along with Ikutaro Kakehashi for their development of the MIDI protocol in 2013. In 2012, Smith was inducted into the Keyboard Magazine Hall of Fame and in 1987 he was named a fellow of the Audio Engineering Society. In January 2015, DSI revealed their latest product, the fully analog Prophet 6, which has been described as a successor to the Prophet 5. The Prophet 6 was the first synthesizer in nearly twenty years to bear the Sequential brand name, following an extremely generous move on the part of Yamaha’s president Takuya Nakata to return the rights of the name to Smith.