Doepfer A-179 Light Controlled CV Source (no longer available) - Manual (Page 5)

doepfer System A - 100 Light Ctr. Volt. Source A-179
5
Light controlled "Theremin"
Fig. 1 shows a ”light controlled Theremin”. In contrast
to the Theremin the pitch (VCO) and loudness (VCA)
parameters are not controlled by the distance to the
antennas but by the illumination of the light sensors of
two A-179s. For details concerning the Theremin
please look at the A-178 user’s guide.
Fig. 1: “light controlled Theremin"
If the light source is located a few meters away from
the sensors it's possible to control them with whole
body movements (e.g. controlling A-179s by dancing).
Module A-179 allows the creation of "environment-
controlled sounds” for special performances, i.e.
sound generation (pitch, timbre, loudness, panning,
clock speed ...) responding to illumination changes
caused by the movement of people or objects.
Using the gate function
The gate function in the A-179 gives you the facility to
have remote switching of events in real time, simply
by changing the illumination in one of the ways
described on the previous pages:
• Start/Stop (e.g. of a sequencer)
• "One-Shot" (ADSR-triggered sound event)
• Switching filter types or VCO waveforms
• Advancing Sequential Switch A-151 to next step
Another example is an audio gate, using the gate
signal to switch a VCA on and off, either directly or via
an ADSR or slew limiter (Fig. 2). Whenever the signal
is below a certain voltage, the VCA simply shuts down.
Fig. 2: User example for the audio gate function
VCA
A-179
cv
VCO
cv
A-179
VCA
A-179
Gate
ADSR
VCO
CV