I play live gigs with the MPC 1000 & like to have separate tracks / channels for the different elements in my beats - Drums / Bass / Keys & samples etc. So I used to use a small 6 channel mixer with the keys & samples (mostly stereo files) going out the main outs, then routing drums & bass through outputs 1 & 2 respectively.
But as I travel for gigs a lot, I figured a better / easier / more portable way to do it would be to just use tracks mutes - Drums track 1, bass track 2, keys / samples track 3 etc. I picked up a cheap little midi hub box to connect an old Akai LPD8 I had knocking around to the MPC midi in, to control the track mutes, using the LPD pads in toggle mode. I actually sounds better quality wise having everything going out the main stereo out to the desk, rather than using the extra mono outs - plus it's more efficient for quick tight drop outs for various elements such as just dropping out the drums on the last half a bar of a sequence. The track mutes also mute the MIDI data rather than the audio, so if I drop out & mute some keys with delay FX on, the mute will stop the samples being triggered but the delay will still ring out, which is the way I like it personally!
I still use an extra out sometimes for aux FX, using an old Roland / Boss Space Echo pedal, if I'm doing some dub or psychedelic style shit!
