ReCycle (REX)

The Stockholm company Propellerhead Software started out with this in 1994, long before Reason. Anyone with a sampler knew the problem: a loop at the wrong tempo either sounded chipmunked or fell out of time. ReCycle found each hit, split the loop there and wrote a MIDI file that triggered the slices in order. Change the tempo and only the triggers moved; the audio inside each slice stayed untouched.

The slices and their positions were packed into the REX format, later REX2 with the .rx2 extension, which was the standard for loop libraries for a decade. For drums it is still the most transparent technique, yet time-stretching and warp markers took over anyway, because they don't need a separate program.