Apple Soundtrack Pro - Manual (Page 155)

Chapter 7 Working in the Waveform Editor 155
To select the entire audio file:
m Choose Edit > Select All.
You can select one channel (left or right) of a stereo audio file, and apply actions to
only the selected channel. You can also select only part of one channel.
To select the left channel of an audio file:
1 Move the pointer near the upper edge of the waveform display.
The pointer changes to the letter “L.”
2 Drag the pointer to select the part of the left channel you want to work with.
As you drag, the right (lower) channel of the audio file becomes darker in the waveform
display. You can also double-click in the upper part of the waveform display to select
the entire left channel.
Left channel selected