Doepfer - A-138BV: Mixer
Module A-138 is a four channel mixer, which can be used with either control voltages or audio signals. Each of the four inputs has an attenuator, and there's a master attenuator, so that the mixer can be used at the end of the audio chain - ie. it can be used to interface directly with an external mixer, amplifier, etc.
A-138 b: potentiometers with logarithmic response, so especially suitable for audio signal mixing.
Width: 8 TE / 8HP / 40.3 mm
Depth: 35 mm (measured from the rear side of the front panel)
Current: +10mA (+12V) / -10mA (-12V)