Hm. If I got you right… Renoise simply does not know.
Most of the samples are already sampled with the right note.
In case the sample it is not set on the right note (it was sampled while the instrument was playing any different note) you can set the right note with the help of 2 parameters… both in the Instrument Settings tab, under the Sample Properties section.
The first is Basenote and it deals with shifting up or down the base note by one entire note each click so that you can search for the right position… but we’re assuming your “different note” is sampled exactly in tune. In case it is not, here comes the second parameter called Finetuning that’s where you can set the pitch of the sample in a very accurate way to adjust very small out-of-tune problems.
Just to know: Renoise consider each sample divided by 255 ( 256? ) steps… and consider the sample in the middle of this range… (so you can alter each sample from +127 to -127)… in order to have: E5 finetuned to +127 it’s equal to F5 finetuned to -127
uhrm… well I guess that’s it
Renoise doesn’t try to know this. It probably defaults to using C4 as the base note, but whatever it is, you can change this base value by hitting the instrument settings tab (F4) and changing Basenote til it sounds correct. There’s also fine tuning stuff in there if your sample is tuned right but everything else if a bit off, or vice versa.