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Doepfer system a - 100, Keyboard control of vca (tracking) – Doepfer A-130/A-131 VCA (linear / logarithmic) User Manual

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doepfer

System A - 100

VCA

A-130 / A-131

7

Keyboard control of VCA (tracking)

You can use the CV output from a keyboard to modu-
late the VCA, and so have level of amplification de-
termined by the pitch
of a note - what’s usually cal-
led keyboard tracking.

In the example in Fig. 7, high frequency notes are
amplified more than low frequency notes. Use control 1
on VCA 2 to vary the degree of keyboard tracking.

Fig. 7:

Keyboard tracking - the higher the pitch, the
louder the output

To produce the opposite effect (that is, inverse keyboard
tracking, where lower sounds are more amplified than
higher ones) patch a Voltage-Inverter A-175 in before
VCA 2 (see Fig. 8).

Set the gain control 1 at maximum, and use CV2
control 2 to determine the intensity of the effect

Fig. 8:

Inverted keyboard tracking: the higher the
pitch, the less amplification.

VCO

mf

p

f

CV

Gat e

VCA 1

CV1

VCA 2

ADSR

VCO

CV

Gat e

VCA 1

CV2

VCA 2

ADSR

mf

p

f

A-175

Gain = 10