I've seen a couple people ask about the "limitations" of 8 audio tracks, and not sure if anyone has properly answered it.
There are 8 audio tracks, but 127 tracks in all. Without reading a manual yet, it seems that on the MPCX, you could have:
- 8 audio tracks
- 64 MIDI tracks (more, maybe, since there is USB MIDI, too)
- 8 cv tracks
- 47 left over for samples, program changes, whatever
The MPC1000 has polyphony of 32 (I believe...if its stereo samples you get 16), so I can't imagine it is less on the new MPCs.
Also, when comparing it to an Octatrack, consider that sequences on MPCs can be hundreds of measures long, in just about any time signature.