7.1

809
Audio Postproduction and Audio Effects
 Audio Playback of Timeline Tr ac k (s) is disabled (Track Header: Audio playback column - is loud-
speaker icon visible?).
 Tr a c k s are routed to incorrect Output Busses (Audio Editor > Audio Mixer > check Output Map-
ping).
 Tr a c k is muted or another Tra c k is set to Solo (check Audio Mixer).
 The clip’s Audio Source Tracks are deactivated (check clip Properties).
 Audio is being suppressed by an insert or send effect, or by a fader in the Tr a c k’s signal path
(audio mixer).
 Clip’s Audio Playback is set to zero or is too soft (view clip in the Clip Viewer > open extended
dialog box and check faders).
 Clip has no audio. Activate the Wa v ef o r m display: No wave means no audio. When recording,
check cables; go to Logging Tool > Audio tab: Is there an incoming signal?
Auxiliary Level in the Taskbar
An auxiliary level is located next to the Audio To o l icon in the taskbar. The two topmost segments in the
four part scale change to red if the outgoing level reaches overload.
Digital Scale and Digital Audio
Digital audio requires different level indicators than analog audio. Avid Liquid works with a digital scale,
designed for a range between 0 dB and minus infinite dB. When working with analog peak level meters,
most of which are designed for a range between +5 dB and -40 dB, you often end up pushing the 0 dB
limit. This is not permitted with digital audio; the -9 dB limit should not be exceeded.
Headroom
With digital audio, overload reserve is called “headroom”. Headroom is not standardized; a headroom of
9 to 12 dB is generally used. The “red” range of Avid Liquid’s peak level meters begins by default at -9 dB.
Digital audio exhibits less tolerance to overloading than analog audio. If you exceed a certain level,
noticeable distortions can be heard or signal information is lost due to clipping. This is particularly
important to keep in mind when converting audio signals, for example, from analog to digital or
between different digital formats.
Peak Level Meter Response Time
Avid Liquid’s peak-monitoring devices are designed with extremely fast response times and register sig-
nal peaks even in the 1 millisecond range. Make sure you do not overload even these brief peaks, other-
wise you may end up with distortions or loss of audio information due to clipping.