Doepfer A-138j Inverting/Interrupting Mixer (Janus Mixer)

The Doepfer A-138j, also known as the Janus Mixer, is a powerful 3-channel mixer designed for advanced signal control, combining inverting mixing and momentary interrupt switching. It is ideal for both audio and control voltage (CV) signals.

Each channel features a center-detent potentiometer that ranges from -1 (inverted) to +1 (non-inverted), allowing for detailed and expressive signal shaping. Each channel also includes a momentary pushbutton, letting you manually mute or engage that channel’s signal on the fly—great for live performance or modular improvisation.

A master output with gain control completes the module, making it a flexible tool for patch routing, dynamic modulation, and real-time interaction in any Eurorack system.

Key Features:

• 3-channel inverting and interrupting mixer

• Center-detent knobs with bipolar control (-1 to +1)

• Momentary pushbuttons to mute/engage each input

• Master mix output with gain control

• Suitable for audio and CV

• Compact 8 HP width – performance-ready