Autodesk 64006-051108-9001 - Discreet Cleaner - Mac, Руководство пользователя

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The Audio Tab 81
Use the Dynamic Range filter in conjunction with the Volume adjustment. The Dynamic Range
is applied first, then the volume is modified, which enables you to encode both ends of the
range of the audio, then increase or decrease its total volume.
For example, you can limit the Minimum to 20% and the Maximum to 90% for a very narrow
dynamic range to make sure the limited audio is as loud as possible without distortion.
Experimentation is the key to finding the best settings given your material and preferences.
Custom Dynamic Range Settings
The Dynamic Range filter Custom option offers three sliders:
•
Minimum Amplitude — controls how the quiet portions of the signal are modified. Zero
leaves the low volume sections unaltered. Higher settings increase the loudness of the
previously quiet sections.
• Maximum Amplitude — alters the volume of the loud parts of the audio. The numbers on
this slider represent the percentage of maximum original volume, which is the same as the
Adjust Volume slider. A setting of 100 leaves the loud portions unaltered, and settings
below 100 reduce the volume of these portions.
• Lookahead — controls how far in advance of the current sample the Dynamic Range filter
analyzes to determine how to modify the current volume. Longer lookahead values create
smoother transitions between altered and unaltered sections of the audio. Smaller values
create shorter and potentially noticeable transitions between sections of the audio. Very
small values may make the audio sound choppy.
Noise Gate
The Cleaner Noise Gate filter completely silences sections of the audio that are very quiet (but
not silent) for a period of time. This is useful for material like narration, which should be totally
silent between sections, but may have background noise.
In addition to Mild, Moderate, and Extreme presets, you can choose a custom setting.
Using the Noise Gate filter is especially helpful in conjunction with variable-bitrate audio
codecs, such as Qualcomm PureVoice, when used for low-bandwidth streaming. This is
because totally silent sections take less bandwidth with variable-bitrate audio codecs.
Therefore, proper use of the Noise Gate with appropriate material can reduce the overall size
of the audio file.
Note:
The Noise Gate filter is also sometimes referred to as a Clamp filter because it clamps
down on the signal below a certain threshold.