Emu XL-7 & MP-7 User's Group

"Note however, that with method 2, notes from your external kybd will
ALWAYS play both the internal A synth channels as well as play your
external synth. This is probably not what you want, but maybe it is."

....Unless you turn the MIDI channel to off, which is what i do. 
Actually I pretty much only use tracks and channels 1-5 for internal 
sounds, so my main multisetup has tracks 6-16 ext and MIDI channels 6-
16 off. Of course you have to turn the MIDI back on if you are trying 
to step sequence an external device, but in this case I have some 
dummy patches with no waveforms selected....I use the same patches to 
arpeggiate external devices also.