I know it's an old thread but here's my method which works well for me and it's pretty straightforward. I record whatever I want in FL Studio and save it using the Edison VST (only using the trim side noise option beforehand). After installing sox and adding it to the path, I run this Windows .bat file from the folder where I saved my .wavs:
cd %~dp0
FOR %%A IN (*.wav) DO sox.exe --norm %%A -b 8 -c 1 -e signed-integer "%%~nA.raw" rate 16754
Where 16754 means C3. If the sample is on a different note, change accordingly - here is a list of the frequencies for each note I got from
http://www.wanda25.de/amiga.html
Note Frequency
C1 4143,6
C#1 4389,7
D1 4654,7
D#1 4926,2
E1 5231,4
F1 5542,0
F#1 5872,3
G1 6222,6
G#1 6592,7
A1 6982,1
A#1 7389,4
B1 7829,8
C2 8287,1
C#2 8779,4
D2 9309,4
D#2 9852,5
E2 10462,8
F2 11084,0
F#2 11744,7
G2 12445,2
G#2 13185,5
A2 13964,2
A#2 14778,7
B2 15694,2
C3 16574,3
C#3 17558,9
D3 18667,9
D#3 19705,0
E3 20864,1
F3 22168,1
F#3 23489,4
G3 24803,5
G#3 26273,3
A3 27928,3
A#3 29557,5
B3 31388,4
This will generate a 8 bit .raw sample from each .wav in the folder. If you don't know the note, Edison (and I guess other similar tools in other DAWs) provides an auto detection tool by clicking on the frequency number which will bring the sample properties dialog.
I have tried resampling, mixing channels, etc beforehand within Edison itself but I haven't noticed any difference in quality in regards to just saving it and then running sox.
Also note I save the samples as raw because OctaMED 5 (which is my tracker of choice) doesn't seem to like the 8svx samples generated by sox, you may change the extension to 8svx intead of raw in the command line and sox will automatically save it in that format.