Description

In this velocity and aftertouch sensitive 5-octave keyboard, the Sequential Prophet 5 embodies all three revisions of the legendary synth: Rev1, Rev2, and Rev3. It features 2 CEM 3340 VCOs per voice, analog Curtis (CEM 3320) filters, and SSI 2140 low-pass filters designed by Dave Rossum.

A pure renewal of an analog classic: the authentic and powerful sound of the original with the precision of a modern, cutting-edge instrument.

Sound Synthesis in the Prophet 5 Rev 4

The oscillators of the Prophet 5 Rev 4 are the source of the warm, deep, and powerful sound that this synthesizer generates. These are not ordinary analog oscillators. The 2 VCOs of the Prophet 5 Rev 4 were designed and built with the same chip used in vintage Prophets: the CEM 3340. It was only in 2016, 9 years after the untimely death of its creator Doug Curtis, that the company he founded decided to reproduce this chip. The two oscillators, called A and B, can generate saw and variable pulse width waves. Oscillator B also features a triangular wave. One of the peculiarities that made this synth famous is the fact that each oscillator can simultaneously play multiple waveforms, resulting in a unique, rich, and full-bodied sound. In the Oscillator B section, there is a switch called LOW FREQ: once activated, it will be able to reproduce very low frequencies, making it usable as an LFO. With the dedicated DETUNE knob, it is possible to vary the pitch of Oscillator B by approximately a semitone compared to Oscillator A. As in previous versions, this Rev 4 also features the ability to synchronize Oscillator A to Oscillator B to create complex sounds rich in harmonics. When we activate the Unison function, the Prophet 5 acts as a monophonic synth: it plays only one note at a time. Use it to create full-bodied, imposing basses and leads, dedicating all five voices to a single note: 10 oscillators per key! Holding down the Unison button will activate the Chord Memory function to store the intervals between notes of a chord, then transpose and reproduce them starting from the note (root) you play on the keyboard.

The Filter Section of the Prophet 5 Rev 4

The SSM 2040 chip used for the filters of the Prophet 5 Rev 1 and Rev 2 was highly appreciated; however, it was not particularly stable and functional. The chip of the third version, the CEM 3320, in addition to its distinctive sonic imprint, made a fundamental contribution to the stability and reliability of the instrument. The characteristics of these two chips were similar: both created a 4-pole resonant low-pass filter, but with different sonic results. In designing this fourth revision of the Prophet, the Sequential team decided to integrate both filters into the instrument. With the Rev button located next to the Cut-off potentiometer, we can freely decide whether to select the Rev 1/2 filter or the Rev 3 filter. The difference between the two filters is by no means subtle, as variables such as different envelope response times come into play. The integrated circuit with which the filter that reproposes revision 3 is built is the same component designed by Doug Curtis in 1979. The SSM 2040 chip of revision 1 and 2 has instead been replaced with its modern counterpart SSI 2140 designed by Dave Rossum.

The Prophet 5's Vintage Mode Knob

In addition to sourcing the original hardware components used in the vintage version of the Prophet 5, Sequential conducted extensive research to determine what made the sound so unique. It was discovered that many of these characteristics were due to slight fluctuations and differences in response times from voice to voice, and not only in the frequencies of individual VCOs but also in the filters, envelopes, and amplifiers. To reproduce all of this in this new Rev 4 of the Prophet-5, Sequential added the Vintage knob: use it to continuously transition from revision 1, the rarest and most capricious Prophet of all, to revision 4: the most stable and precise version ever.

Poly Mod & Enhanced Unison

Beyond the unmistakable tone of its oscillators and filters, much of the classic sound of the Prophet 5 comes from the results of the connections that the Poly Mod section allows us to achieve. Faithful to the original, the modulation sources are the filter envelope and oscillator B. Destinations include oscillator A frequency, oscillator A pulse width, and filter cutoff. It is called Poly-Mod (polyphonic modulation) because the Prophet can play up to five voices, meaning that each voice must apply the programmed modulation to the selected destination. For example, if we set oscillator B to LO FREQ mode, we will have just created 5 LFOs: one per voice. At this point, we activate keyboard tracking and each of these LFOs will modulate the destination with a different frequency speed from note to note. The range of possible sounds defies its simplicity. Another welcome and famous mode in the Prophet 5 is the Unison mode, which now features a configurable number of voices from one to five with variable detuning and chord memory.

Velocity and aftertouch on the Prophet 5

Although the mission of Sequential was to make the new Prophet 5 as accurate, authoritative, and faithful to the original as possible, they could not resist adding a couple of modern improvements to increase expressiveness: velocity sensitivity and aftertouch. These allow the new Prophet 5 to do things the original never could: filter sweeps, LFO mod, and volume changes at your fingertips, without taking them off the keyboard.

Prophet 5 Programming

The panel of this keyboard synthesizer presents a knob for each function, thus allowing immediate access to all sound shaping controls. With the PRESET button, we can enter LIVE PANEL MODE: the sound of your Sequential Prophet 5 will automatically switch to the values corresponding to the physical settings of the knobs and buttons you see on the panel. What you see is exactly what you hear. 200 permanent factory programs and 200 rewritable user programs are included, which also include the set of 40 original presets from 1978. Sounds that made history, used in countless recordings and film soundtracks from that era to the present day.

Prophet 5 Keyboard and Connections

All this analog power is housed in a robust chassis with a five-octave (61 full-size keys) semi-weighted Fatar keyboard, MIDI inputs and outputs via DIN and USB, Gate and CV. Since each Prophet 5 is built with hand-selected woods, the image and color may vary from piece to piece, thus making each instrument unique and unrepeatable.

Sequential Prophet 5 Keyboard Features

    
• 5-voice polyphonic analog synth
    
• Premium full-size 5-octave Fatar keyboard
    
• Semi-weighted, with velocity and aftertouch (mono)
    
• 200 user and 200 factory memories
    
• 2 VCOs (CEM 3340) per voice
    
• OSC A saw, variable pulse width
    
• OSC B saw, triangle, variable pulse width
    
• Waveforms can be played simultaneously on both oscillators
    
• Hard-sync
    
• Unison and Chord Memory
    
• 2 resonant 4-pole LP VCFs (SSI2140/CEM 3320)
    
• Rev1/2 or Rev3 filter selection button
    
• 1 LFO, 2 ADSRs
    
• Wheel-Mod 2 sources 5 destinations
    
• Poly-Mod with 2 sources and 3 destinations
    
• Vintage Knob
    
• Glide
    
• Master Tune and tune button
    
• MIDI: In, Out and Thru DIN, USB type B
    
• Main mono output (1/4'' TS jack)
    
• Headphone output (1/4" TRS stereo jack)
    
• 2 CV in/out; 2 GATE in/out
    
• 1 1/4'' TRS jack input for expression pedal (Amp Volume)
    
• 1 1/4'' TRS jack input for expression pedal (Cutoff Filter)
    
• 1 1/4'' TS jack input for sustain pedal
    
• Dimensions and weight: 94.92x41.52x15.11cm; 14.51KG
    
• IEC connector for power supply
    
• Consumption: max 20W