DOEPFER / A-132-8 Octal VCA

Variations

This module is made by the German synthesizer manufacturer Doepfer. It's a VCA designed for building polyphonic patches.

The A-132-8 Octal Poly VCA is a VCA designed for building polyphonic patches. It features four channels of VCA pairs, each consisting of VCAs connected in series.

The first VCA has a linear control scale, while the second VCA can be switched between linear and exponential control scales via a jumper on the back of the unit. Typically, one VCA is needed for the volume envelope, and another for velocity (or volume CV control, AM, etc.), hence the design with two VCAs per voice.

The following controls and inputs/outputs are included:

Default Gain 1 (GL)

Default Gain 2 (GX)

CV Input VCA1

CV Input VCA2

Audio Input

An additional total audio output is also available.

This module provides two default gain controls (GL, GX) to open the first VCA (L) and the second VCA (X). The GL and GX knobs generate two internal default control voltages (0 to +10V) connected to the switching contacts of the 1L-4L jacks (Control GL) and 1X-4X jacks (Control GX), respectively. Unless cables are connected to the jacks, the internal default control voltage (GL or GX) is used to control the corresponding VCA. This is necessary when each VCA is not in use (no external CV available). Without this function, the VCA would always be closed, preventing signal output even if other VCAs in the channel are open. Control GL and GX are also useful for testing polyphonic patches (such as VCO tuning).

■Width: 8HP
■Depth: 45mm
■Current Consumption
+12V: 40mA
-12V: 40mA