A-138m Matrix Mixer

Doepfer's 4 x 4 matrix mixer in 20 HP: four inputs, four outputs and a knob at each crossing, each output switchable between attenuators and polarizers.

Key features

• Four inputs (rows 1 to 4) and four outputs (columns A to D)
• Sixteen knobs: how much of each input reaches each output
• A switch per output: unipolar (the knobs attenuate) or bipolar (the knobs are polarizers, nothing at the centre, inverted to the left)
• DC coupled, for audio and control voltages alike
• With nothing in Input 1, the four top knobs give DC offsets (an internal jumper, fitted ex works)