Apple Final Cut Express HD - Manual (Page 638)

638 Part VIII Audio Mixing
How Audio Recorded With the Voice Over Tool Appears in Your Sequence
Audio is recorded during the pre- and post-roll each time you use the Voice Over tool,
giving you extra audio for trimming at the head and tail. Each clip has a 5-second
handle at the head and a 2-second handle at the end. By definition, handles do not
appear in the sequence clip, but are visible if you open the clip in the Viewer. In the
Viewer, you’ll see that the In and Out points for that clip match the beginning and end
of the specified recording duration. The extra handles are there if you need to extend
the clip head or tail.
5-second
pre-roll
In point Out point 2-second
post-roll
Placed in Timeline