Sequential Circuits is an American company producing synthesizers of high quality and nice functionality and was founed by Dave Smith, an engineer and musician, in 1978. Thanks to its creator the company entered the music history as a MIDI implementation pioneer turning MIDI into communication basics for all the modern electric music instruments, and as a vector synthesis technology progenitor – this type of synthesis developed in Prophet VS, the last Sequential Circuits synthesizer right before the company closed down. The idea was picked up straight away by Yamaha and Korg in the late 1980s.
Prophet-5, the first analog synthesizer with microprocessor, became the best example of the successful business of Sequential Circuits as well as very soon became widely popular among musicians and is still as popular today. The instrument was the №1 competitor in the industry where the big Japanese trio Yamaha-Roland-Korg together with the ambitious American brands Moog, ARP, Oberheim put the music world into a cold-war-like bipolar status. Prophet-5 offered soft sound and great interface.
First Sequential Circuits instruments were sequencers and programmable devices for synthesizers. In 1974 the analog sequencer Model 600, digital sequencer Model 800 and Model 700 Programmer appeared.
The legendary polyphonic analog synthesizer Prophet-5 smashed the music world in 1978. The instrument became the heart and soul of Dave Smith’s lifetime's work, the foundation for programmable synthesizers and analog equipment. The synthesizer was given internal memory to save and store your own patches. Prophet-5 included 5 voices of polyphony getting renowned as one of the first polyphonic synthesizers on the music market. Prophet-5 turned out to be the first fully programmable analog synthesizer with microprocessor as well. The instrument offered memory for 40 patches and two voltage-controlled oscillators, an ADSR envelope generator. The instrument comprised a 61-note keyboard (not a dynamic one), pitch/mod wheels, 40 patches to save the parameters. This synthesizer set the standard for all the programmable polyphonic synthesizers. The monophonic synthesizer Pro-One released in 1980 included all the functions polyphonic Prophet offered.
The next model of the series is Prophet-10 which combined all the possibilities of Prophet-5 with a polyphonic sequencer and just doubled them, there were two versions: the model with one keyboard and the model with two keyboards. Trying to repeat the success of the first Prophet model another great Prophet 600 model contributed into the popularity of the brand – it was the first synthesizer to support MIDI. The version included 100 patches to store sounds. The next model, Prophet T8, became known as the first synthesizer with the MIDI piano-type keyboard. The keyboard of the instrument consisted of 76 full size keys with aftertouch being velocity sensitive as well; a simple sequencer. Prophet 2000, the model launched in 1985, and Prophet 3000 (1987) were 12 bit and 16 bit samplers and sported the same functions the previous models of the series did. The synthesizer Prophet VS, released in 1986, was the first synthesizer to feature vector synthesis – the type of synthesis which comes from audio signal morphing which allowed to create rich and compound timbres. The interface included a special joystick which made sound modelling control as easy as it can be.
While still in business the company used to sell products together with the Italian brand SIEL. There wasn’t such a concept yet which is called now badge engineering (or rebadging), but that’s exactly how the new production – Fugue keyboard launched in 1979 and orchestral synthesizer Prelude released in 1982 - entered the music market. Sequential products occupied the higher price niche but the management wanted to invade the segment of affordable synthesizers as soon as possible having no intention to invest into development and production.
The brand didn’t stop creating their instruments though. Sequential Circuits released the first programmable effect module Pro-FX which became quite popular among guitar players.
Six-trak and MultiTrak synthesizers, released by the company, appeared to be the first and the second multitimbral synthesizers respectively on the music market. Unlike polyphony, multitibrality allows to tell how many different instrumental parts can sound every time they can be heard.
Nevertheless despite those series which brought success to Sequential Circuits the brand couldn’t make it any further: the company went broke in 1987 and was eaten by Yamaha corporation. Dave Smith considered his experience in Sequential Circuits a springboard for his career and founded Dave Smith Instruments where the technologies of the legendary Prophet-5 served as inspiration for such yet-to-be instruments as Evolver and following Prophet models – analog (Prophet ‘08) and hybrid ones (Prophet 12, Pro 2). After Yamaha appeared to be so kind (thanks to Roland) and gave back the rights to their previous owner (to call Dave Smith’s synth a Sequential as old good times used to allow him) - Prophet 6 came out. Sequential Prophet 6 was released warming Dave’s heart and pleasing all the fans of his exquisite engineering talent. Prophet 6 is sort of a modern Prophet 5 rethought to suit our needs. The instrument offers new interface: all the control elements let you access all the parameters immediately. The model included new effects of studio quality, polyphonic step sequencer, good arpeggiator.
Another influential name in the history of the brand is John Bowen. In the late 1980s he started to work in Korg and participated in the flagship project creating famous digital workstations of that time – Wavestation; then he took part in Oasys development which has been a foundation for every top Korg synth until now; a little bit later in the mid-2000s he built his own digital mega synth John Bowen Synth Design Solaris which had no alternatives. And will never have.
