Doepfer A-100(~ 40 MB) - Manual (Page 84)

A-102 • A-103 System A - 100 doepfer
4
4. In / Outputs
! CV 1
Socket CV 1 is the filter’s standard voltage control
input, and works on the 1V / octave rule, like the
VCOs. If you patch a modulation source (eg LFO,
ADSR) to this input, the cut-off frequency of the filter
will be modulated by its voltage: ie., the sound color
changes according to the voltage put out by the modu-
lator. If you use the VCF as a sine wave oscillator,
connect the pitch CV into this socket. Do the same if
you want the filter’s cut-off frequency to track exactly
with the pitch of a note (filter tracking).
" CV 2 • § CV 3
Sockets CV 2 and CV 3 are also voltage control
inputs for the filter. Unlike CV 1, you can control the
level of voltage - the intensity of modulation effect on
the filter - with attenuators 2 and 3.
$ Audio In
This is the filter’s audio input socket. Patch in the
output from any sound source (eg. VCO A-110/A-111,
Sampler/Wavetable Oscillator A-112, Subharmonic
Generator A-113, Ring Modulator A-114, Audio Divider
A-115, Waveform Processor/Waveshaper A-116/ A-
136, Noise Generator A-117/118, external audio signal
e.g. via A-119, VC Divider A-163, mixed signal of
different audio sources using A-138 and so on).
% Audio Out
Filter output % sends out the filtered signal.
5. User examples
As the A-102 and A-103 are very similar to the A-120
please refer to the user examples of the A-120. The
filter’s cut-off frequency can be modulated in various
ways. The basic modulations types are:
• VCF - LFO (A-145, A-146, A-147)
Cyclical changes of the sound spectrum
• VCF - ADSR (A-140, A-141, A-142)
Modulation by an envelope results in triggered gra-
dual change of the sound spectrum
• VCF - Keyboard CV
This modulation produces pitch-related filter ope-
ning: the higher the pitch, the more the filter opens,
and the brighter the sound becomes.
But even other voltage sources may be used to control
the frequency of the A-102/103: e.g. Theremin A-178,
Light-controlled CV A-179, Joy Stick A-174, MIDI-to-
CV interfaces A-190 or A-191, Random Voltage A-
118, S&H A-148, Sequencer A-155, Quantizer A-156,
Foot Controller A-177, Ribbon Controller A-198 and
many more. Please refer to the user’s guides of these
modules for details and additional examples.