There is a little about it in the manual, here are a few finding I did with my particular configuration. I used MIDI Monitor for tracking.
Configuration:
Octatrack MKII 1.30c.
All audio track midi channels are OFF.
Audio CC out: Int
Audio Note out: Int
Prog Ch Send: OFF
OT controls a few MIDI synths.
- At power on OT sends PC message 0 on the PC Channel if set to a particular number. Certainly unexpected because I explicitly turned it off.
- If the PC Channel is AUTO, at power on OT sends PC message 0 on the highest MIDI channel from the configured MIDI track. For instance if you have configured MIDI tracks 1 and 5 to send PC, it will send on channel 5. Completely unexpected and potentially very disruptive. Fortunately it is overwritten by the subsequent PC for the loaded part but it may not be always so.
- If nothing is set on MIDI tracks, OT sends PC 0 on channel 1.
- The same behavior is at turning OFF. And here the things get really scary. Imagine you just found that sound on your three synths working together but did not save the patches. You turn the OT on and that sound is gone. What’s worse, after an inspirational jam at 3am you switch the OT off and at least one sound is lost unless you never use channel 1 for PC and never switch programs from OT.
- Bank select uses only CC0. Some synths react only to CC32 (with CC0 set to 0), so for them MIDI track settings are useless.
- Finally, the way the patterns send the PC is weird. Each pattern just sends its number as a PC on the track’s MIDI channel. I see very few practical uses of this.
What I’d like to see is the ability to send both bank select (coarse and fine) and PC messages as parameter locks on any MIDI channel from any MIDI track. Thus I could switch programs on one track at the opportune time from any other track.