Pianos / Synthesizers
SYNTHESIZER
Modular synths / sound modules
DOEPFER/A-133-2 Dual VC Polarizer Slim Line

DOEPFER / A-133-2 Dual VC Polarizer Slim Line

Variations

A-133-2 Dual VC Polarizer is a 2CH polarizer that can control voltage. Although it is a slim version of the A-133, it has several additional features and improvements compared to the A-133.

The A-133-2 Dual VC Polarizer is a 2-channel voltage-controlled polarizer. It is a slimmed-down version of the A-133, but it has several additional functions and improvements compared to the A-133.

The A-133-2 can be used in a wide range of applications. It can be used as a simple VCA, a voltage-controlled polariser/attenuator, a voltage-controlled inverter, or even as a DC-coupled ring modulator. The principle of the module is that it is equipped with two special voltage-controlled amplifiers (VCAs), which can amplify in both positive and negative directions.

The overall amplification is controlled by the sum of the voltage generated by the ‘Man’ control, the externally input CV, and the position of the CV control, which acts as an attenuator for the externally input CV. When there is no externally input CV, the amplification rate when the ‘Man’ control is turned fully clockwise is +1. At the centre position, the amplification factor is zero, and when turned fully counter-clockwise, the amplification factor is -1 (the input signal is inverted). The manually adjusted amplification range can be modulated by an externally applied CV. The CV can be set to either positive or negative (i.e. bipolar) to obtain a positive or negative amplification value controlled by the external CV.

Furthermore, the CV signal can be modulated via the modulation control input Mod using another CV. This means that if there is no plug connected to the Mod socket, a constant positive voltage is used as the modulation CV. The CV range of this socket is bipolar and can be adjusted to the user's requirements using the trimming potentiometer. The factory setting is -5V ~ +5V. (-5V = no modulation, 0V = approx. 50% modulation, +5V = full modulation)

The current amplification is indicated by a two-colour LED. This is not a signal indicator, but indicates the amplification (yellow = positive amplification, red = negative amplification).

Typical uses
Voltage controlled amplifier (VCA) capable of pure positive amplification (Man + CV)
Voltage controlled inverter capable of pure negative amplification (Man + CV)
Voltage controlled polariser/attenuator Overall amplification (Man + CV) that varies between positive and negative
DC-coupled ring modulator with offset function, set the Man control to 0 to obtain ‘classic’ ring modulation
Additional effects using the modulation function of the CV signal (using the Mod input)

Width: 4HP
Depth: 40mm
Current consumption:
+12V: 20mA
-12V: -20mA