Korg D1200/D1600 inputs question...

Now I heard the 1200 has 4 ins and the 1600 has 8.
Can anyone explain why a 12 track recorder has 4 ins and a 16 track recorder has 8 ins?
Does each in have seperate track information? Like could I have 1 output from the ASR 10 going into 1 input on the recorder, and still have each of 8 ASR 10 instruments on their own track?
My MPC doesn't have 8-outs yet, but could I have different MPC Sequencer Tracks go to their own track on the D1600, all through one input?

Does that make sense?
In other words how do you utilize 12 or 16 tracks if you only have 4 or 8 inputs?
Thanks.

Yes you should be able to. I forget how many tracks that thing has,but i know its more than enough. With your Mpc your goin to have to record them 1 by 1 to different tracks. Its possible there's a way around it,but without the 8-outs that may be the only move.

You are gonna have to record your music in multiple takes, one for each instrument, unless you got the 8 outs and the 1200, where you'll do them in groups of four instruments at a time, or if you got the 8 outs and the d1600 you can do them in groups of 8 instruments at a time.

Word.
Multiple takes, I see.
Appreciate.