Apple Final Cut Pro 5 - Manual (Page 1466)

Chapter 9 Diagnostic Tools for Clips 115
I
Detecting Audio Peaks
When you capture audio, clipping occurs if any part of the audio signal goes over 0
decibels full-scale (dBFS). Because 0 dBFS is the maximum digital level possible, all
levels that would have been above 0 dBFS are set (clipped) at 0 dBFS. Due to the
nature of digital audio recording, such clipped audio typically results in a crackly, brittle
sound. Excessive peaks indicate that your audio was recorded at unsuitable levels.
If your program has peaks in the audio, you can either recapture the audio at a better
level, or edit the audio appropriately to avoid them. You can use the Mark Audio Peaks
command to identify audio peaks in your clips. It’s then up to you to decide whether to
not use those sections of audio or rerecord them. For information about recording at
proper levels, see Volume III, Chapter 4, “Audio Levels, Meters, and Output Channels.”
Note: Final Cut Pro analyzes levels taking your clips’ audio volume levels into
consideration. For example, if you set a clip’s audio level to +12 dB, audio peaks may be
detected. However, if you reset the audio level adjustment to 0 dB, there may no longer
be audio peaks detected.
To find and mark audio peaks:
1 To detect peaks in a clip, do one of the following:
 Select one or more clips in the Browser.
 Open a sequence clip from the Timeline.
2 Choose Mark > Audio Peaks > Mark.
A status window appears with a progress bar showing how much of the process is
complete. Markers are placed at each peak.
 If you selected a clip in the Browser, markers appear for the clip and are labeled “Audio
Peak N,” where N starts at 1 and increases, depending on how many audio peaks are
detected. These markers also appear in the Viewer, when the clip is opened there.
Audio peak markers
for a clip selected
in the Browser