Manual

doepfer
System A - 100
VCO
A-110
3
3. Basics
Module A-110 puts out four waveforms simultaneously.
All these signals have the same pitch, since all are
controlled by the same voltages present at inputs "
and §.
Sawtooth
The VCO’s sawtooth waveform is present at output &.
It has a ‘cutting’ sound, rich in overtones. All the
harmonics of the fundamental are present, with a linear
reduction in intensity as the harmonic series progres-
ses - so that the second harmonic is half as
Fig. 1: Harmonic spectrum of a sawtooth
strong, the third is one third, the fourth a quarter, and
so on (see Fig. 1).
Sawtooth waves are ideal for synthesizing sounds
which are rich in harmonics, such as percussion, brass
or vocal timbres.
Square wave
The VCO produces a square / rectangle wave at output
/. You can alter its pulse width manually, or by voltage
control (Pulse Width Modulation).
Fig 2: Square waves with different pulse widths
f
1
f
2
f
3
f
4
f
5
f
6
f
7
f
8
ff
9
Harmonics
➨
0%
100%
1/f 1/f
a
b
c