Timbre Shift; Playback Mode; Alternative Switch (Altcontrol And Altmethod) - Kurzweil PC3 Musician's Manual

Many, but not all, PC3 sample roots have been pre-assigned a carefully chosen, fixed alternate
sample start or end point that can be selected using the Alternate Switch feature (altControl
and altMethod parameters). This feature allows you to control the sample playback start/end
time triggered by any control source.
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