Is there any way to turn MOXF into multitimbral tone generator?
Place the MOXF is either SONG or PATTERN mode. This makes it a Multi-Timbral Tone Generator.
I thought I got it right with SONG mode but it turns out it just sets up output midi channels, rather switching channels on and off.
You did have it right. The MOXF doesn’t switch channels on and off, YOU have to switch the MIDI Channels.
Press [SONG] or [PATTERN]
Press [F1] VOICE
Press [SF2] MODE
Here you can set the MIDI Receive Channel for each of 16 Parts... use Track buttons - to view the sixteen Parts.
Receive Channel can be set to any Channel 1-16, or Off.