Apple Soundtrack Pro 3 - Manual (Page 443)

About Options in the Preprocessing Pane
Preprocessing options are applied to the audio data before encoding. With the exception
of the Compression Preset setting, leave these settings at their default values unless you
have a specific technical reason for changing them. The following export options are
available in the Preprocessing pane:
• Compression Preset pop-up menu: Specifies one of the dynamic range processing modes
built in to the Dolby Digital Professional (AC-3) format. The default of Film Standard
Compression should only be used when you are encoding an original mix intended for
cinema. In almost all cases, you should choose None.
Choose a compression
setting from the
Compression Preset
pop-up menu.
Important: It is critical that you have set the Dialog Normalization setting correctly in
the Audio pane if you intend to use any of these Compression Preset settings. The
Compression Preset settings assume that the audio, after the dialogue has been
normalized, is at the normal listening level of 31 dBFS. Levels that are consistently
louder than that result in distorted sound and erratic levels.
Note: If you are building a Dolby Digital Professional 5.1 channel surround sound DVD,
you will use Film Standard Compression.
• General: Select the Digital Deemphasis checkbox to specify whether input audio data
is pre-emphasized and needs to be de-emphasized before encoding.
• LFE Channel: Select the Low-Pass Filter checkbox to apply a 120 Hz low-pass filter to
the Low Frequency Effects (LFE) channel. Turn off this filter if the digital signal fed to
the LFE’s input does not contain information above 120 Hz.
443 Chapter 20 Exporting Multitrack Projects