A-132, System a - 100, Doepfer – Doepfer A-100(~ 40 MB) User Manual
Page 350: Dual low cost vca, Midi-controlled vcf or vca envelope amount, Audio signal amplitude control

A-132
Dual Low Cost VCA
System A - 100
doepfer
4
MIDI-controlled VCF or VCA envelope
amount
One important use of the A-132 is to control a VCF or
VCA envelope according to how much velocity CV a
MIDI-CV interface is putting out, as in Fig. 2.
Fig. 2:
Controlling the level of a VCF or VCA enve-
lope by the velocity CV output from a MIDI
interface.
Audio signal amplitude control
For non-critical applications, the A-132 can also be
used for amplifying audio signals.
In the example in Fig. 3, an A-132 is patched in to
make the level of noise in an audio signal voltage-
controlled. The control voltage CV
N
could for instance
come from the velocity output of a MIDI-CV interface;
or from an envelope, for a chiff at the start of each
note.
Fig. 3: Audio signal amplitude control
VCO
A-118
CV
A-132
N
A-138
A-132
VCF /
VCA
Velocity CV
MIDI-
Interface
ADSR
Gate
Audio-
Signal