Doepfer A-126 VC Frequency Shifter (no longer available) - Manual (Page 5)

doepfer System A - 100 VC Frequency Shifter A-126
5
6. User examples
A typical use for a frequency shifter is to transform the
human voice - for instance, in a simple example, to
produce ‘robot voices’.
A kind of vibrato effect can be produced by modula-
ting the frequency-shift with a slow sine-wave from an
LFO (frequency about 5 - 7 Hz).
More drastic effects can be produced by replacing the
sine wave with a sawtooth (frequency about 1 - 2 Hz)
to produce a repeated rising modulation.
With the patch in fig. 1 you can ‘roughen up’ audio
signals (e.g. voices) by modulating the frequency-shift
with colored noise, and sending the original and the
frequency-shifted signals to a mixer, to control the
amount of ‘harshness’ or ‘edge’.
With the patch in fig. 2, you can create a new type of
percussive stereo effect, using the square wave from
an LFO (frequency c. 5 - 6 Hz) to modulate the
frequency-shift and continuously alter the side-bands.
The Up and Down outputs are sent to left and right
stereo channels respectively.
fig. 1: "roughening up” an audio signal
fig. 2: percussive stereo effect
VCFS
Up
A-118
Audio-
Signal
CV In
A-138
Colored
VCFS
VCA L
Up
Down
VCA
LFO
Audio-
Signal
R CV In