4.2

during output.
DC filter: Select this checkbox to apply a DC (direct current)
high-pass filter to all input channels. Although this filter
provides a simple way to remove DC offsets, note that most
mixed audio material is already free of DC offsets.
Surround channels: 90 phase-shift: This checkbox, which
applies a 90-degree phase shift to the surround channels, is
selected by default. The shift in phase decorrelates the front
and back channels and prevents the L and Ls signals from
canceling each other out if a surround-compatible downmix is
later applied to the decoded signal.
Surround channels: 3dB attenuation: Select this checkbox to
apply a 3 dB cut to the surround channels during output. This
option is intended for multichannel output (like a film
soundtrack) that is being transferred to a consumer home
theater format. Cinema surround channels are mixed 3 dB
“hot” (higher) relative to the front channels to account for
cinema amplifier gains.
Dialog normalization: Enter a value in the field to set the
loudness of the program in your sound files relative to full
modulation. The playback device uses this information to
maintain similar loudness among different AC-3 streams. The
goal is to give all AC-3–encoded audio files the same listening
level, regardless of the source file.
Audio effects
For a list of available audio effects and instructions on how to add
an audio effect to a setting, see .Add and remove effects