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A Guide to the EMS Product Range
1969 to 1979

by Graham Hinton

Last updated: 17 June 2001

The Products

• VCS3 (aka The Putney)
• VCS4
• DK1 (aka The Cricklewood)
• Synthi KB1
• Synthi 100
• Sequencer 32
• Sequencer 164
• Sequencer 128
• Synthi Sequencer 256
• Pitch to Voltage Converter
• Eight Octave Filter Bank
• Triple Slew Limiter
• Two-Voltage Random Generator
• The Other VCS4
• Synthi A
• Synthi AKS
• DKS
• KS
• Synthi Hi-Fli
• Synthi VCS3 II
• 32 x 32 Matrix
• 49 x 49 Matrix
• Synthi P
• Spectron (formerly Spectre)
• Computer Synthi
• Synthi E
• Synthi DKE
• QUEG - Quadrophonic Effects Generator
• Phase Frequency Shifter
• Vocoder 5000 (aka Studio Vocoder)
• Universal Sequencer
• Vocoder 2000
• PolySynthi
• PolySequencer

Most of the photos are black and white originals and have been scanned as a 256 colour greyscale. They are best viewed the same.
Click on the small images to view the full high resolution ones.

[Key to prices: (Price when introduced) 1979 Price]

London geography lesson: Peter Zinovieff lived in Putney, David Cockerell lived in Cricklewood, the BBC Radiophonic Workshop was located in Delaware Road and Portabello Road was (and still is) a fashionable market.

VCS3 (aka The Putney)

VCS3.GIF (207K)

• 3 x Voltage Controlled Oscillators.
• Noise Generator.
• 2 x Input Amplifiers.
• Ring Modulator.
• Voltage Controlled Low Pass Filter.
• Trapezoid Envelope Generator.
• Voltage Controlled Reverberation.
• Meter.
• 2 x Stereo Output Amplifiers.
• Joystick.

VCS4
1969. Not produced.
Designer: David Cockerell.
VCS4.GIF (277K)
A "Live Performance Module" comprising two VCS3s side by side with a keyboard, mixer and signal processing in front all in a single wooden cabinet. There was only one prototype built, lost track of in 1983, but now known to be in the USA.

DK1 (aka The Cricklewood)
1969. (£145)
Designer: David Cockerell.
Velocity sensitive "Dynamic" monophonic Keyboard for use with VCS3.
Included an extra VCO and VCA.

Synthi KB1
1970. (£330) Not produced.
Designer: David Cockerell.
KB1.GIF (353K)
The same circuit modules as the VCS3 housed in a different case with a 29 note miniature keyboard, Prototype sold to Yes.

Synthi 100 (formerly Digitana, aka the Delaware)
1971. (£6,500) £35,000
Designer: David Cockerell.
SYNTHI100.GIF (224K)
Synth100 (heavily modified) with Computer Synthi (1977)

The same technology as the VCS3, but built into a very large console patched with two 60 x 60 matrix boards, one for the signals and one for control voltages.
Module complement:

• 12 x Voltage Controlled Oscillator.
• 2 x Noise Generator.
• 3 x Ring Modulator.
• 4 x Voltage Controlled Low Pass Filter.
• 4 x Voltage Controlled High Pass Filter.
• 3 x Trapezoid Envelope Generator.
• 2 x Voltage Controlled Reverberation.
• Octave Filter Bank.
• Slew Limiter.
• Envelope Follower.
• Pitch to Voltage Converter.
• 8 x Input amplifiers.
• 8 x Stereo Output amplifiers.
• 2 x Joysticks.
• 2 x 5 octave Dynamic Keyboards.
• 256 step digital sequencer.
• Oscilloscope.
• Frequency meter/counter.

<40 built. Sold mainly to Universities and radio stations, the most famous and overworked model belonged to the BBC Radiophonic Workshop and was the main synthesizer used throughout the 70s. Listen to their special showcase program "The Space Between", the original Hitchhikers' Guide to the Galaxy radio series or any John Pertwee vintage Dr. Who episodes.

Several of the devices were packaged separately as small wooden sleeved units:

• Pitch to Voltage Converter (£70)
• Triple Slew Limiter
• Eight Octave Filter Bank (£80)
• Two-Voltage Random Generator (£125)

Sequencer 128 (also 32 and 64 versions)
1971. (£135)

DIGSEQ.GIF (187K)
Prototype of what became the Sequencer 256
Peter Zinovieff and Tristam Cary walked into the Moog Trumansberg factory with this and just plugged it in, to much surprise and annoyance - their sequencer could only do 8 steps.

Synthi Sequencer 256 (formerly Synthi Moog Sequencer)
1971. (£1,100)
Designer: David Cockerell.
SEQ256.GIF (346K)
Separate version of the Synthi 100 sequencer.

• 3 Layers with 2 Control Voltages plus Key Parameters
• Fourth Key only Layer
• Five Octave Velocity Sensistive Keyboard
• 256 Event x 42 bit Memory
  Each event comprises 2 x 6-bit Control Voltages and 13-bit Start & Stop times
• Internal (0.1 - 200 Hz) or External Clock
• Plays Forwards and Backwards
• Editing

The other VCS4
1971. Not produced.
NOTASA.GIF (240K)
A design study for a follow up to the VCS3 case containing the same boards.This was believed lost until it recently appeared in Sound on Sound Oct 97/p190. When this was being considered some engineers from the EMS factory arrived carrying a briefcase which turned out to be the prototype Synthi A. There was no contest.

Synthi A (formerly Portabella)
1971. (£198)
Designer: David Cockerell.
Industrial Design: Gerry Rogers.
Same specification and pcbs as the VCS3, but fitted in an attache briefcase. (Yes, it actually is a Spartanite one.)
PORTABEL.GIF (483K)
The prototype Synthi A. Note the name, the meter and the lid loudspeaker.

Synthi AKS
1972. (£420) £1,452
Designer: David Cockerell.
Synthi A with a KS sequencer in the lid.
SYNTHIA.GIF (204K)
Synthi A with original K and Sequencer32
The first 30 Synthi AKs featured a black and silver Touch pad, Spin-and-touch random note selector and an unplayable resistive touch sensitive keyboard. This was replaced by the familiar blue capacitive touch sensitive keyboard with integrated sequencer.

DK2
1972. (£145) £472
Designer: David Cockerell.
"Duophonic" version of DK1.

DKS
1972. Not produced.
Designer: David Cockerell.
DKS.GIF (162K)
A mechanical keyboard version of the KS sequencer.

KS
1972. (£164)
Designer: David Cockerell.

The sequencer from the Synthi AKS available separately.

• 30 Note touch sensitive dynamic(!) keyboard
• Real Time & Sequencer Pitch Outputs
• 256 step x 6 bit memory (5 bits for keyboard + 1 for Key)
• Sequence length range: 700ms to 100s.
• Transposition controls.

Synthi Hi-Fli (formerly Sound Freak)
1973. (£180) £308
Designer: David Cockerell.
Industrial Design: Martin Holbrook.
HIFLI.GIF (128K)
A guitar treatment unit built as a console on a stand with two pedal controllers which could be routed as control voltages to any of the slider functions.

Main Controls and Effects (Left to right on control panel)

• Top Boost Slider to provide up to 30db boost at high frequencies. The output from this section goes to the Octave Shift, Sustained Fuzz and Ring Mod sections.
• Octave Shift Slider mixes in a Sub Octave signal.
• Buzz Switch adds high frequency overtones to the sub octave signal.
• Ring Mod Slider mixes in a signal an octave up when single notes are played or "ring modulated" effects on chords.
• Decay Rate Rotary control for the decay time of Ring Mod and Octave Shift signals.
• Sustain Fuzz Slider mixes variable upper harmonics.
• Attack Rate Rotary control varies the rise time of the sustained fuzz signal.
• Pedal Switches Each switch routes either the left or right pedal to voltage control the Slider above it. Each switch also has an inverted setting so that single pedal movements can produce complimentary effects.
• Solo/Strum Switch to alter the Hi-Fli's sensitivity to playing style.
• Bypass Mix Central Slider to blend the effects and original signal.
• Modulation Selector Rotary Switch selects: Slow Modulation range, Fast Modulation range, Rising Mod envelope, Falling Mod envelope, Rising Ramp and Falling Ramp.
• Treatment Selector Rotary switch selects: VIBRATO, PHASING 1, PHASING 2, WAA-WAA (single resonant peak), WAW-WAW (six resonant peaks) and MEOW (two sets of three peaks in opposite directions).
• Modulation Speed Slider to fine control the modulation rate.
• Modulation Ramp Time Slider to set ramp time between 0 and 5 seconds.
• Modulation Depth Slider controlling depth of modulation applied to Phase Filter.
• Frequency Shift Slider to bias the symmetry of modulation.

Mains powered: 100-135 or 200-260 Vac
Input Signal: 10mV (min) to 3V (max), 100kohm impedance.
Output Signal: -20dbm (min) to 0dbm (max).

Synthi VCS3 II
1973. (£374) £1,268
Designer: David Cockerell.
Prestopatch added, matrix layout and some circuitry changed, otherwise same as VCS3 Mk I.

32 x 32 Matrix
1974. (£450)
Designer: David Cockerell.
32X32.GIF (197K)
Patchboard for interconnecting two VCS3s or Synthi As by plugging into the Prestopatch sockets.

49 x 49 Matrix
1974. (£583)
Designer: David Cockerell.
Larger version of above with keyboard sockets.

Synthi P
1974. Not produced.
Designer: David Cockerell.
SYNTHIP.GIF (349K)
A MkIII "Professional" version with improved Oscillators, Filter and Envelope.
Only 3 prototypes made, 2 in this form with bronze finish, the other in standard Synthi A case and styling.

Speech Synthesizer
1974. Not produced.
Designer: David Cockerell.
SYNTHIS.GIF (127K)
Prototype with graphic Formant entry (drawn with a ballpoint pen!).

Spectron (formerly Spectre)
1974/5. (£4,000)
Designer: Richard Monkhouse.

SPECTRE.GIF (198K)

• Digital Matrix Patch Panel: 53 inputs by 57 outputs.
• Analogue Matrix Patch Panel: 16 by 20.
• Manual, VCO and Audio controls.
• Digital counters, delays and video modifiers.

The prototype was used to provide a projected lightshow for an early Tangerine Dream concert at the London Rainbow.
15 Built.

Computer Synthi
1975/6. (£15,000, software extra)
Designer: Peter Eastty.
An add-on to the Synthi 100 interfaced to the control matrix board via two 24 x 60 matrix boards. Complement:

• PDP8/M with 4K RAM
• Twin digital cassettes.
• 24 Input ADCs.
• 24 Output DACs.
• 16 Slider CV Inputs.
• Switch button Panel.
• LED Display.

3 Built.

Synthi E
1975. (£200) £558
Designer: Tim Orr
A low cost "Educational" synthesizer in briefcase format.

• 3 x VCO 1Hz - 10kHz.
• LFO
• VCF LP - BP - HP / Oscillator.
• Trapezoid Generator.
• Noise, Inverter, Mixer, Modulator, Internal monitor.
• Manual Tape Controllers

Synthi DKE
1975. £200
Designer: Tim Orr
A 3 octave mechanical keyboard for Synthi E.

QUEG - Quadrophonic Effects Generator
1975. (£1400)
Designer: Tim Orr.
QUEG.GIF (160K)
Four channel quad surround sound mixer with joystick and quadrature VCO control. A two channel version was also made fitted into a custom Electrosonic EMS Mixing Console.

Phase Frequency Shifter
1975. (£400).
Designer: Tim Orr.
Separate version of the one in the Vocoder 5000.

Vocoder 5000 (aka Studio Vocoder)
1976 (£5,000) £7,165
Designer: Tim Orr.
VOCODER.GIF (367K)
Custom version built into Synthi 100 for WDR Germany (Stockhausen)

• 22 Band Filter + Follower + Modulator Filter with 22 x 22 matrix patchboard.
• Mic/Line Input, 2 Oscillators & Noise sources.
• Voiced/Unvoiced detector and slew/freeze control.
• Pitch to Voltage Extractor.
• Frequency Shifter.
• 3 PPM meters, Spectrum display driver and comprehensive interfacing.

Universal Sequencer
1977. (£700)
Designer: Tim Orr.
UNISEQ.GIF (250K)
Upgraded KS with Control Voltage and Gate interface.
Few built.

Vocoder 2000
1977. £813
Designer: Tim Orr.

• 16 Band Filter + Follower + Modulator Filter.
• Mic/Line Input, Oscillator & Noise sources.
• Voiced/Unvoiced detector and slew/freeze control.

VCS3/Synthi A Upgrade Cards
1978. Not produced.
Designer: Graham Hinton.
Replacement circuit boards featuring improved VCOs with temperature compensation and synchronisation, improved VCAs, RM and Reverb.

PolySynthi
1978. (£700) £1,200
Designers: Peter and Rose Zinovieff, (Delay by David Cockerell)

• Four Octave keyboard with Aftertouch.
• Four Octave Oscillator Bank.
• Noise and External input with envelope follower.
• 2 x VC LFO.
• 2 x VC ADSR.
• 2 pole/4 pole VCF.
• VC Analogue Delay.

<30 built.

PolySequencer
1978. Not produced.
Designers: Peter Zinovieff and Graham Hinton.

Microprocessor based polyphonic sequencer with up to 10 minutes recording capacity.
Real time editing and effects.
2 prototypes built.

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All material on these pages Copyright ©1995 - 1998 Graham Hinton & Robin Wood.
Most photos are from the EMS Archive and have never been used before.

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