I need to get an audio interface and I'm highly considering the Duet because I'm on a mac and I here it is great. Although I will be recording from my MPC 2KXL. Will I need MIDI to record from my XL?
What else wouldn't I be able to do without MIDI?
Just buy a little USB midi port for your mac, they're cheap.... Hook your MPC up to it, plug in the Duet, good to go (after a bit of midi configuration in your DAW - I'm guessing Logic with the Mac and Duet?)
No you will not need midi inputs on duet to record anything audio... unless you wanna record midi...
umm I dont really get you but just get a standalone midi interface, they are very cheap... and dont worry about what you might miss out on...
If you are coming out of the MPC using balanced audio signals, you dont need an additional midi interface... but if you wanna control soft synths by bashing on the mpc then you will need a midi interface....
Technically you could just load the MPC samples into logic and sequence there... either keep the mpc as a glorified drum pad or get, say, a korg padkontrol (mine is still kicking after about 4-5 years, great value considering) or the AKAI midi pad, I forget what it's called, but probably has a more similar action / look to what you're used to.
Another option would be to spring for something a little more multi-channel - ensembles can be had for $1200 - $1500 on eBay, or there are several other options. If you got an interface with digital I/O, you could use the MPC that way - it has digital outs, right?
Any way you cut it, though, you're going to want midi. Others have suggested the cheapo USB cords, and those are fine, actually, but you could either get midi with your interface or look at something like the M-Audio Midisport series - options from 1x1 to 4x4 I think (1 to 4 midi ports, 16 channels each, leaves a lot of room for your expansion or use with multiple synths simultaneously - depends on your needs).
PS: I get that the MPC is a staple in some types of music - that's cool, but it's arguably redundant with a computer. Keep it for the vibe or the workflow if you want... no judgements either way.
More on topic to what you're originally asking -- I think the Duet is really cool but it gets overrun very quickly - as in only 2 inputs / outputs and no digital, and impossible to add more firewire interfaces. As soon as you need to record more than one thing at a time, you're done. Ensemble is a much better value, really.
In my opinion trying to sync up all the fine points of external synths / samplers (including something like the MPC) has been a huge pain in the arse - I had some high-end synths here for a while and it was usually more trouble than it was worth to handle the midi and audio I/O, recall every time, all that jazz - for ME the computer is a much more competent and convenient sampler for my workflow. I think external sound modules are pretty out-moded, but some people cling to them for various reasons, and that's fine, but if you do be prepared to either work exclusively in the confines of the unit (your MPC in this case) or do some fancy MIDI footwork to get it all rolling.