Logic Pro 9 User Manual - Help Library - Apple

To select a particular section of an audio file
µ Click-hold the start or end of the area you want to select in the waveform display, then
drag to the right or left.
The start point and length are displayed (as sample words) in a help tag while you make
your selection.
To extend an existing selection area
Do one of the following:
µ Choose Edit > Select All Previous (or use the corresponding key command).
µ Choose Edit > Select All Following (or use the corresponding key command).
To define the selected area using a region
1 Select a region in the Audio Bin or Arrange area.
2 Choose Edit > Region → Selection.
This function is useful if you want to reselect the entire region for cycled playback—after
performing a number of edits, for example.
The reverse can also be done, allowing you to redefine the length of an existing region
by choosing Edit > Selection → Region.
You can modify selections by changing their start or end points, or you can move the
entire selected area completely.
Note: If you choose Edit > “Snap Edits to Zero Crossings,” any length adjustments to
audio region start or end points will snap to the nearest zero-crossing point of the
waveform. For more information, see Snapping Edits to Zero Crossings.
Chapter 17 Editing Audio in the Sample Editor
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