This one came from the community. And they were right to ask.
Zenteek could technically read 5.1 files. But technically is doing a lot of work in that sentence. The moment audio hit the DSP chain, everything collapsed to stereo. M/S decoding, Stereoize, Crossfeed - all of it was built for two channels.
Version 1.4.1 - New paths
There are now two distinct audio paths. I restructured the entire signal chain to make this work and had to adjust some of my Audio Units to go along.
Native 5.1 and 7.1 material goes through Direct Pass-Through - most DSP modules step aside and the signal reaches your interface intact. No unnecessary processing, no silent channel collapsing. What was mixed in surround plays back in surround. The temporarily disabled devices are labeled during native multichannel playback.
For stereo material, there's Upmix. A matrix-based processor - inspired by Pro Logic and DTS Neo topologies - expands the stereo field across your speaker layout. Wide mode pushes lateral spread aggressively with a narrower center. Music is more vocal forward. Hall has more of a concert hall depth.
New Operational Modes
The UI change that makes this work is the Mode switch in Output Tools.
Headphone mode gives you Crossfeed and Room simulation. Speaker mode gives you channel selection and the channel mixer. These are different listening contexts and they've always deserved different controls. Crossfeed and Reflection simulation makes no sense on a 5.1 system. Each channel gets its own gain control in the mixer, so you can tune the balance to your room rather than accepting whatever the algorithm decides.
Multi-channel support requires a multi-channel interface. If you're running a USB DAC with two outputs you can't activate these features.
This was a meaningful architectural change, in a good way.
Enjoy!