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System a - 100, A-110, Basics – Doepfer A-110 Standard VCO User Manual

Page 3: Doepfer, Sawtooth, Square wave

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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

f

f

9

Harmonics ➨

0%

100%

1/f

1/f

a

b

c