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SCI Prophet 5.jpg
Dates1978–84, 2020–
PriceUS$3,995 (Rev 1, 2)
US$4,595 (Rev 3)
US$3,499 (Rev 4, 5-voice, 2020)[1]
Technical specifications
Polyphony5 voices
Oscillator2 VCOs per voice
Synthesis typeAnalog subtractive
Analog FM (Poly-Mod)
Filter4-pole resonant low-pass
AttenuatorADSR envelope (2)
Aftertouch expressionNo on Rev1 to Rev3, Yes on Rev4
Velocity expressionNo on Rev1 to Rev3, Yes on Rev4
Storage memory40 patches (120 patches on later units, 200 patches on the Rev4 iteration)
Keyboard61 keys
Left-hand controlPitch and modulation wheels
External controlCV/Gate
Proprietary serial interface
MIDI (Rev 4 only)

The Prophet-5 is an analog synthesizer manufactured by Sequential. Designed by Dave Smith and John Bowen, the Prophet-5 was the first fully programmable polyphonic synthesizer and the first musical instrument with an embedded microprocessor. Between 1978 and 1984, about 6,000 units were produced across three revisions. In 1981, Sequential released a 10-voice, double-keyboard version, the Prophet-10. Sequential introduced new versions in 2020.

The Prophet-5 has been widely used in pop and rock music. It has been emulated in software synthesizers and analog hardware.


The Prophet-5 was created in 1977 by Dave Smith and John Bowen at Sequential Circuits, who aimed to create the first polyphonic synthesizer with patch memory.[2] Initially, they developed the Prophet-10, a synthesizer with ten voices of polyphony; however, it was unstable and quickly overheated, creating tuning problems. Smith and Bowen removed half the electronics, reducing the voices to five and creating the Prophet-5.[2]

Smith demonstrated the Prophet-5 at NAMM in January 1978 and shipped the first models later that year.[3] Unlike its nearest competitor, the Yamaha CS-80, the Prophet-5 had patch memory, allowing users to store sounds rather than having to reprogram them manually.[4]

Three versions were built between 1978 and 1984. The first, Revision 1, was hand-assembled and produced quickly to generate initial revenue; only 182 were made. Revision 2 was mass-produced in quantities over 1,000; this model was more robust, added cassette patch storage, and replaced the koa wood casing with walnut.[2] Revision 3 replaced the Solid State Music (SSM) chipset with Curtis Electromusic Specialties (CEM) chips, necessitating a major redesign. According to Sound on Sound, Revision 3 "remained impressive and pleasant to play, but was slightly cold and featureless by comparison to earlier models".[2] In all, approximately 6,000 Prophet-5 synthesizers were produced.[2]

In the Prophet-10, a pair of Prophet-5 sound boards provide ten voices

In 1981, Sequential Circuits released the Prophet-10, featuring 10 voices, 20 oscillators, and a double manual keyboard. Like the Prophet-5 Revision 3, it uses CEM chips.[2] The first Prophet-10s used an Exatron Stringy Floppy drive for saving patches and storing sequencer data. Sequential later moved to a Braemar tape drive, which was more reliable and could store about four times as many sequencer events.[2]

The Prophet-5 was equipped with a proprietary serial interface that allowed the user to play using the Prophet Remote, a sling-style keytar controller, but the interface cannot connect the Prophet-5 to other devices. Sequential produced a MIDI interface that could be retrofitted to later versions of the Prophet-5 Revision 3. Third-party MIDI interfaces have also been offered.[2]

In 2020, Sequential announced a new version of the Prophet-5, the Rev 4. The Rev 4 adds features including USB and MIDI connectivity, velocity and aftertouch sensitivity, polyphonic glide, two sets of filters (both modern versions of the original SSM and CEM filters used in the rev 1/2 and rev 3; now selectable via a toggle switch) and a "vintage" knob to recreate the instability of various synthesis parameters that gives the older instruments a distinctive sound.[5] Sequential also announced a new Prophet-10, a ten-voice monotimbral version of the Rev 4, unlike the earlier double-manual bi-timbral Prophet-10.[1]


The Prophet-5 became a market leader and industry standard.[4] It has been used by musicians including Tony Banks,[6] Phil Collins,[7] Michael Jackson, Tangerine Dream, Madonna, Patrick Cowley, Dr. Dre,[4] Too Short, Radiohead,[8] John Carpenter, Alan Howarth, Nena,[9] and John Harrison.[4] Brad Fiedel used a Prophet-10 to record the soundtrack for The Terminator (1984).[10] Peter Gabriel considered the Prophet-5 his "old warhorse" synth, using it for many sounds including the prominent synth intro of "Sledgehammer".[11]


Early Prophet-5s used voltage-controlled oscillator (VCO), filter and amplifier chips designed by E-mu Systems and manufactured by Solid State Music (SSM). Revision 3 Prophet-5s used Curtis CEM chips manufactured by Curtis Electromusic Specialties. Some owners maintain that SSM oscillators produced a richer timbre.[12] However, the SSM oscillators rendered the instruments unstable and prone to detuning over time. CEM chips have remained more stable.[13]

The Prophet-5 uses five voices of polyphony. Each voice is assigned two VCOs. Both oscillators can generate sawtooth waves and square waves (with variable pulse width), and the second oscillator can also generate a triangle. The oscillators can be played in sync, or in "Poly-Mod", with oscillator B and the filter ADSR envelope modulating the frequency, pulse width, and filter of oscillator A. A dedicated low-frequency oscillator (saw, square, or triangle) is also present to modulate the pulse width and/or pitch of oscillators A and B and filter cutoff frequency.[12]

Hardware re-issues and recreations[edit]

Sequential Prophet-6 (2015)

In January 2015, Smith announced that Yamaha's president, Takuya Nakata, had granted him rights to the Sequential brand, which he had been unable to use following the company's acquisition. The release of the name coincided with Smith's debut of the Prophet-6, a new synthesizer based on the Prophet-5 with additional features.[14]

In 2020, Sequential re-issued the Prophet-5 and 10. Unlike the original version of the Prophet-10, the new version only featured a single manual keyboard, but retained the same ten voices of the original. Enhancements to the original include:

  • 200 programs, up from the original's 40;
  • a switch allowing the user to change between the original Rev 1/2 and Rev 3 filters;
  • a "Vintage" knob that could be used to alter the sound characteristics between four different revisions of the Prophet-5;
  • a semi-weighted keyboard produced by Fatar that adds both velocity and mono aftertouch, and
  • Full MIDI implementation.

Initial shipments of the instrument were recalled by Smith after it was discovered that a hardware flaw in the new machines caused a decrease in the synth's higher registers. Smith suggested the problem got by him because he no longer hears higher frequencies like he used to. Sequential offered to fix the affected units, which consisted of desoldering two capacitors on the mainboard, or even replacing the entire synth. The flaw was limited to serial numbers 1-195 for the Prophet-5, and 1-159 for the Prophet-10.[15]

Software emulations[edit]

Arturia developed a softsynth version of the Prophet-5, the Prophet V. Prophet V also includes a recreation of the Prophet VS, a synthesizer manufactured by Sequential Circuits in 1986. Elements of the two synthesizers can be combined in a "hybrid" mode. The softsynth closely recreates the layout of the original analog synthesizer, though there were some differences in programming, notably through some restrictions on the envelope generator.[16]


  1. ^ a b "Prophet-5 Returns!" (Press release). San Francisco, California: Sequential. 30 September 2020. Retrieved 13 October 2020.
  2. ^ a b c d e f g h Reid, Gordon (March 1999). "Sequential Circuits – Prophet Synthesizers 5 & 10 (Retro)". Sound on Sound. Archived from the original on 3 February 2016. Retrieved January 23, 2015.
  3. ^ Preve, Francis (23 July 2012). "Dave Smith in His Own Words". Keyboardmag. Archived from the original on 2013-06-11. Retrieved 2018-10-17.
  4. ^ a b c d "The 14 most important synths in electronic music history – and the musicians who use them". FACT Magazine: Music News, New Music. 2016-09-15. Retrieved 2018-10-17.
  5. ^ "Sequential Prophet 5 Product Page". Retrieved 5 October 2020.
  6. ^ "Tony Banks talks new album A Chord Too Far and his favourite synthesizer of all time". Musicradar. Future Publishing Limited. Retrieved 2020-10-20.
  7. ^ "Classic Tracks: Phil Collins' "In the Air Tonight"". Mixonline. 2005-05-01. Retrieved 2020-09-01.
  8. ^ "The 14 synthesizers that shaped modern music". The Vinyl Factory. 2014-03-04. Retrieved 2018-03-05.
  9. ^ Paul Tingen. "John Carpenter - Film Director & Composer". Sound on Sound. No. July 2016.
  10. ^ Seth Stevenson, What Is the Time Signature of the Ominous Electronic Score of The Terminator?, Slate, Published 26 February 2014, Accessed 27 February 2014.
  11. ^ Hammond, Ray (January 1987). "Peter Gabriel - Behind The Mask". Retrieved February 20, 2021.
  12. ^ a b "Sequential Circuits Prophet 5". Vintage Synth Explorer. Retrieved 2015-12-26.
  13. ^ Forrest, Peter (1996). The A-Z of Analogue Synthesisers Part Two. Short Run Press Ltd. p. 114.
  14. ^ "Sequential is Back!". Dave Smith Instruments. January 22, 2015. Retrieved January 23, 2015.
  15. ^ Rogerson, Ben (October 28, 2020). "Dave Smith confirms that there's a problem with the new Prophet 5 and Prophet 10 synths: "We screwed up"". MusicRadar.
  16. ^ Reid, Gordon (September 2006). "Arturia Prophet V". Sound on Sound. Retrieved January 23, 2015.

Further reading[edit]

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