sub mixes

hi,

coming from the mpc 3000 i am right now recording the single samples to reaper with the ren.
my prcedure is that i route a sample to a submix, eg drums sub 1 and than subsequently export it
as an audiofile. this i do for all samples... it takes a lot of time, if i have like 20-30 samples.

so is there any other way to do this? OR how do you export your tracks to mix it in the daw?