Hi
I dont have a clue about different effects on different channels but...

There are effects,3 I think that are documented in the manual page 114-115 for the DJX but not selectable from the DSP on the display.

If you hear anything about hidden voices pls email me at ulf.bergwik@exertus.se

I havent heard about hidden voices yet but I had to search the web (this discussion page amongst other) in order to find out how to get the sequencer software to set voices outside General MIDI.

Regards

Uffe