Manual

LM2 (optional)
Loudness Pilot English Manual (2014-10-07) 99
Fig. 47.: Fig. 2: Target loudness based
on a consumer’s Dynamic
Range Tolerance
Fig. 2 shows target loudness for selected broad-
cast platforms based on a consumer’s Dynamic
Range Tolerance (DRT). The aim is to center
dynamic range restriction around average loud-
ness (in this case the -20dB line), thereby avoid-
ing washing out differences between foreground
and background elements of a mix. Please note
how different the broadcast requirements are
from those of cinema.
When production engineers realize the bound-
aries they should generally stay within, less dy-
namics processing is automatically needed dur-
ing distribution, and the requirement for main-
taining time-consuming metadata at a broadcast
station is minimized.
In broadcast, the goal is to use the same loud-
ness measure for…
►
Production,
►
Ingest,
►
Linking,
►
Master Control Processing and
►
Logging.
Using the same loudness measure for all these
purposes ensures better audio quality – not only
in DTV audio, but across all broadcast platforms.
LM2 and TC processing can coexist with PPM
meters, VU meters or Dolby’s LM100 meter. LM2
greatly increases the usability of LM100 in pro-
duction environments because it provides run-
ning status, and gives a standardized and in-
tuitive indication of both dialog and non-dialog
program.
LM2 – Basic Use
LM2 can be used with mono and stereo material
for any type of program material.
It visualizes…
►
short-term loudness,
►
loudness history and
►
long-term statistical descriptors.
To bring up the Radar display:
►
Select the M1 (Meter 1) or the M2 (Meter 2)
tab depending on which of the two Loudness
meters you want to display.
►
Select the Edit page.
►
Select the Radar subpage.
During normal operation, you will be using this
page most of the time. The basic functionality of
the LM2 Radar page is shown in Fig 3.