STMix solves the common space constraint of mixing multiple stereo sources within a modular system. It provides four fully featured channels capable of handling true stereo or normalled mono signals without demanding excessive rack real estate. When you patch a cable into the left input only, the internal circuitry automatically duplicates the signal to the right channel, allowing you to seamlessly integrate mono oscillators or single-voice filters alongside true stereo effects modules.

The control interface focuses entirely on efficient leveling, featuring an independent volume potentiometer for each of the four channels. To maintain its compact size, the module omits dedicated pan pots, meaning signals remain fixed in their native stereo position or centered if mono. This makes the module highly efficient for straightforward leveling and mixing of pre-panned stereo sources, such as multi-channel samplers, stereo delays, or dual-filter architectures.

For growing systems, the module includes a dedicated pair of auxiliary inputs. These line-level AUX inputs pass directly to the master output stage without a volume control, allowing you to cascade multiple units together or introduce a fifth pre-leveled stereo source into your mix. A dual-LED meter monitors the master output bus in real time, giving you immediate visual feedback so you can prevent clipping before the signal leaves your rack.