CHAPTER 9. TEMPO CONTROL AND WARPING
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The warp modes are different varieties of granular resynthesis techniques. Granular resyn-
thesis achieves time compression and expansion by repeating and skipping over parts of
the sample (the grains ). The warp modes differ in the selection of grains, as well as in the
details of overlapping and crossfading between grains.
Let's investigate which warp modes work best for different types of signals and how to
adjust the warping controls for clean stretching. It's also fun to misuse these controls
to achieve interesting artifacts instead of accurate stretching.
9.3.1
Beats Mode
Beats Mode works best for material where rhythm is dominant (e.g., drum loops as well as
most pieces of electronic dance music). The granulation process is optimized to preserve
transients in the audio material.
Use the
Preserve
control to preserve divisions in the sample as boundaries when warping.
For the most accurate results, particularly with percussive material, choose Transients. This
setting uses the positions of the analyzed (or user-created) transients to determine warping
behavior. To preserve speci c beat divisions regardless of the sample's contents, choose
one of the xed note values. For some interesting rhythmic artifacts, choose large note
values in conjunction with pitch transposition.
The Transient Loop Mode chooser sets the looping properties for the clip's transients:
Loop Off
Each segment of audio between transients plays to its end and then stops.
Any remaining time between the end of a segment and the next transient will be silent.
Loop Forward
Each segment of audio between transients plays to its end. Playback
then jumps back to a zero-crossing near the middle of the segment and continues looping
until the time when the next transient occurs.
Loop Back-and-Forth
Each segment of audio between transients plays to its end.
Playback then reverses until it reaches a zero-crossing near the middle of the segment, and
then proceeds again towards the end of the segment. This pattern continues until the time
when the next transient occurs. This mode, in conjunction with the Preserve Transients
selection, can often result in very good quality at slower tempos.