I've had Garritan Jazz Big Band for a number of years but have never really mastered it (using it with LogicProX). I'm trying to create a small band arrangement and am struggling with some basics. What I'm struggling to understand is how the ensembles map against midi channels in Logic. Like, if I assign Logic Track 10 to Aria Player, and then select Sax Section, I don't understand how a single Logic channel can receive or play back all the voices in an ensemble. 

I went onto Youtube and looked for Aria Player tutorials, but there aren't many of them, and the User Manual doesn't have specific info on this question. Any tips or starting-points appreciated.