I am a proper beginner at this game but i have developed this technique as a first way of doing it - work out the bpm by putting say a kick on each beat, then matching a long sample from the tune to be sampled (say 2 bars) while tapping the tempo or matching it by ear and adjusting manually... so as you peeps already said...but i see a massive advantage in having the bpm exactly matching the sample (or adjusting sample to bpm of course), as i like to chop say 32 killer and varying sections of a record (on the computer 1st wont catch me doing THAT on the 3000 haha) and then you can create endless variating bars in real time and be sure that everything you drop in is already exactly in time (and then pick what works out of a much wider possibility) ...i have no training at all but this would seem to be fundamental to me...otherwise you are trying to fit a round peg in a square hole musically speaking - yes you can make it work but its effortless with the bpm set exactly right! effortlessness is what master musicians aim for...i got a LOONG way to go
