thanks, i appreciate the follow
from my understanding, interpolation basically removes the artifacts that come from playing samples at different pitches, or lower bitrates. turning it off can give the sound a really sharp, glassy feel, common with oldschool jungle.
here's an example: https://clyp.it/dbxh3mzk. the first amen break has interpolation on, the second one doesn't, leaving it way crunchier! sounds much better in my opinion.
and something that helped me big time learning trackers was looking at other people's mods. they're huge insights as to how certain effects are done, irregardless of what specific tracker you're using. bogdan raczynski has a big .zip of his tracker files out there somewhere, and sites like aminet.net have archives of files. oldschool jungle mods are my favorite to look through, it's amazing how some people got such huge sounds out of just 4 channels and a couple megabytes worth of samples. renoise is compatible with most old tracker formats, so you can load them in a look at them no problem, even rip the samples out for some oldschool flavor