Doepfer A-130-4 Quad VCA

Module A-130-4 contains four linear VCAs with a common level control section for all four VCAs. It can be used for all applications of simultaneous amplitude/level control of up to four different audio or CV signals. A-130-4 is the replacement of the no longer available module A-132-2. Compared to the A-132-2 the width has been reduced from 8HP to 4HP.

The module has these controls and in/outputs available:

• Control Man.: manual control of the amplification

• Control CV: attenuator for the control voltage applied to socket CVo socket Input 1

• Sockets In 1...4: VCA inputs 1...4

• Sockets Out 1...4: VCA outputs 1...4

Application examples:

• simultaneous amplitude/level control of up to four different audio or CV signals

• polyphonic application 1: simultaneous control of the frequency modulation depth of 4 VCOs (Quad-LFO A-145-4 or Quad-VCLFO A-147-5 > A-130-4 > FM inputs A-111-4)

• polyphonic application 2: simultaneous control of the pulsewidth modulation depth of 4 VCOs (Quad-LFO A-145-4 or Quad-VCLFO A-147-5 > A-130-4 > PWM inputs A-111-4)

• simultaneous control of quadrophonic signals

Technical notes:

• The maximum amplification for each VCA is about 1 ("Man." control fully CW). Even with an external control voltage applied to the CV input the maximum amplification is limited to 1.

• The module is equipped with two internal connectors (pin headers with 4 pins each). Pin header #1 can be used to normalize the four inputs to other modules (e.g. Quad LFO A-145-4 or A-147-5, Quad ADSR A-143-2). Pin header #2 can be used to connect the four outputs to other modules. 

• The max. level at the VCA inputs without clipping/distortion is about 20Vpp or +/-10V.