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Chapter 8 EVOC 20 PolySynth 153
In 1979, Roland released the VP 330 ensemble/vocoder keyboard.
The late 1970s and early 1980s were the heyday of the vocoder. Artists who used them included
ELO, Pink Floyd, Eurythmics, Tangerine Dream, Telex, David Bowie, Kate Bush, and many more.
On the production side, vocoders could—and can still—be picked up cheaply in the form of kits
from electronics stores.
From 1980 to the present, EMS in the UK, Synton in Holland, and PAiA in the USA have been—
and remain—the main yers of the vocoding ag.
In 1996, Doepfer in Germany and Music and More joined the vocoder-producing fraternity.
From the late 1990s to the present, a number of standalone and integrated software-based
vocoders—like the EVOC 20—have appeared.
EVOC 20 block diagram
This block diagram illustrates the signal path in EVOC 20 TrackOscillator and EVOC 20 PolySynth.
Analysis
source
Track
------------
Side chain
LR
Stereo to mono
TO:
pitch analysis
Sensitivity
TO:
Max/Quant./
Glide
Analysis section
Synthesis section
U/V
detection
PS:
MIDI
keyboard
Noise,
N + Synth
Synthesis
source
EVOC20 PS:
Poly synth
pitch
Level
Frequency range between highest/lowest
1-5
Envelope
follower
1-5
A
B
Freeze
Stretch
Resonance
Shift
Filter bank with five bands
(example)
Level
Stereo
width
L
R
Filter bank
input
Filter bank with five bands
(example)
Voltage-
controlled
Oscillator 1-5
LFO
EVOC20 TO:
Tracking oscillator
Track or side chain
Blend
LFO
Parameter control
Legend
Audio signal
Control signal