Since: Apr 08, 2004
Welcome to HRC,
Yes, the piano is sending out MIDI data, which will be picked up inside your computer. Cubase and/or FL Studio shouldn't have a problem picking up the midi data and recording the data as a midi file, or playing the midi data back in a synth or soundfont. actually, it can do both as the same time.
The yammw10 shouldn't have a problem with any multitracker. It wouldn't be useful if it didn't =).
I believe the yam-mw10 (and 12) will only send 2 tracks to the computer, even though it can input many more. I think they get mixed down to 2 inside the mixer, then sent out the usb as 2. The sound quality should be fine, as yamaha makes pretty good preamps (for the consumer market).
I'm thinking you meant a standalone guitar preamp, like a bogner, or such. You can output the preamp to the line in on the mw10, or line in to the ux1 or 2. You wouldn't need to use the preamp on the sound interface.
As far as the line 6, the UX2 has 2 preamps, and it offers tonnes of effects and modelling that the mw10 doesn't. From what I've heard, the UX boxes do a mighty fine job of modelling too, so there's that.
If you were using an external guitar preamp, I'd probably say that it will be better than the line 6. That's just my opinion, but I'm thinking many here will agree.
hope that helps