kerkenat
Bristol_Jonesey
What vsti are you using to generate your audio?
I am using battery 3.
The main reason to seperate the MIDI drums can be ease of editing or to process thru seperate synths as Konrad mentioned. If you were seperating the MIDI drums just to subsequently render each to a seperate wave file then it may have not been necessary.
Most synths support multiple outputs.
When you insert Battery 3 a Properties page comes up first, choose All Synth Audio Outputs instead of First Synth Audio Output. Now you can select a pad, say the snare, and assign it to a seperate output which you can find right under the main fader in the bottom right corner of Battery (ex. Output 1-2). It will now output the snare to a seperate audio track. You can do the same with kick, hats, cymbals etc. You can have each tom output to it`s own track or have them share a track for example.
This now allows you to render all tracks at once with each output going to a seperate track although you don`t have to convert to wave until mixdown if you prefer. You also have the added advantage of processing drums individually as Bristol Jonesey pointed out, seperate effects, EQ etc. on each drum, but this way you also have MIDI functionality if you want to tweak and edit the drums.
If Battery 3 is already inserted you have to save the kit, delete the instance of Battery, insert a new one with the All Synth Audio Outputs option checked and re-load the kit. Probably too late but you`ll know in the future.
My apologies if you knew this already but from what was written I wasn`t sure.