Adobe AUDITION 1.5 - Manual (Page 254)

CHAPTER 12 246
Scripting and Batch Processing
Setting options on the Normalize tab
Use the following options in the Normalize tab to specify how you want to normalize the
waveforms:
Normalization Specifies whether to normalize to an average level or a specific level you
enter in decibels.
Note: The Normalization option doesn’t use percentages, unlike the Normalize effect, because
it is RMS-based rather than peak-based.
Use Equal Loudness Contour Applies an equal loudness contour, where the middle
frequencies are most important. Because the human ear is much more sensitive to
frequencies between 2 kHz and 4 kHz, two different pieces of audio with the same RMS
amplitude but with different frequencies will have different apparent volumes. Select this
option to ensure that audio has the same perceived loudness, regardless of what
frequencies are present.
Out of Band Peaks Determines how Adobe Audition handles out-of-band peaks. When
you amplify audio, the audio samples may extend beyond the clipping point. If out-of-
band peaks occur, you can choose to just let it clip the waveform (and cause distortion),
or you can apply limiting to those areas so the audio doesn't clip the waveform (a common
practice for TV commercials so they sound louder).
• No Limiting (Clip) prevents limiting, so clipped (distorted) audio might occur.
• Use Limiting applies the Hard Limiter, if needed, to keep out-of-band peaks from being
clipped. This options provides two additional options: Look Ahead Time and Release Time.
• Lookahead Time specifies the number of milliseconds generally needed to attenuate
audio before reaching the loudest peak.
Note: If this value is too small, audible distortion might occur. Make sure that the value is at
least 5 milliseconds.
• Release Time specifies the number of milliseconds needed for the attenuation to
rebound 12 dB (or roughly the time needed for audio to resume normal volume if an
extremely loud peak is encountered).
Note: A setting of 200 milliseconds works well to preserve low bass frequencies. If the setting is
too high, audio may stay quiet and not resume normal levels for a while.
Statistics RMS Width Specifies the length of the audio selection to use for calculating the
RMS (Root-Mean-Square) minimum and maximum values.
ug.book Page 246 Tuesday, March 16, 2004 1:29 PM