Apple Soundtrack Pro 2 - Manual (Page 205)

Chapter 6 Editing Audio Files 205
Adjusting Selections to a Zero Crossing
A zero crossing is a point in an audio file where the amplitude is zero. When you edit an
audio file in the File Editor, if the beginning or end points of your edit do not occur at a
zero crossing, the edited audio file can have unwanted noise at the beginning and/or
end of the edited area. Subsequent editing of the file, such as normalizing or increasing
the gain, can increase this unwanted noise.
Once you have made a selection in the File Editor, you can fine-tune the selection so
that it begins or ends at the nearest zero-crossing point.
To adjust a selection to the zero crossing:
1 Make a selection in the File Editor.
2 Choose Edit > Adjust Selection to Zero Crossing and choose one of the following from
the submenu:
 Inward
 Outward
 In Point to Left
 In Point to Right
 Out Point to Left
 Out Point to Right
The edit point is adjusted to occur at the specified zero-crossing.
Moving Between Selections
You can select different areas of the audio file to apply different actions or to play different
areas. Any selection can include the same part of an audio file as another selection. As you
work on the audio file, you can move back and forth between selections.
To move to the previous selection:
m Click the Previous Selection button above the waveform display.
The previous selection becomes the current selection. The selection area appears
darker than the rest of the waveform.
To move to the next selection:
m Click the Next Selection button above the waveform display.
The next selection becomes the current selection. The selection area appears darker
than the rest of the waveform.
Next Selection button Previous Selection button