Bs.1770 Safety Limiter - Orban OPTIMOD 6300 Operating Manual

OPTIMOD 6300 DIGITAL
preset, turn the Loudness Controller off, and then save the result as a User Preset.
Using one of the 6300's remote control mechanisms (like its GPI inputs), recall the
"with loudness controller" and "without loudness controller" presets as desired.
Turning down the L
dramatic impact of loudness transients in dramatic programming; it can let gunshots
and the like through while still constraining long-term loudness to a fixed threshold.
While this is an easy solution that does not require your automation system to tell
the 6300 when to recall presets, it is not ideal because there are some short-term
loudness events, like sibilance, applause, and whistles, that can be annoying to audi-
ences. You can use the Speech-Mode B4 and B5 compressor threshold controls to ac-
complish the same goal.
Another loudness control strategy is this: Instead of using two presets with and
without loudness control (as described above), you can create presets with different
settings of the L
L T
OUDNESS HRESHOLD
programming and a faster attack (70%) for commercial breaks. This will maintain
some automatic loudness control for dramatic programming while controlling the
loudness of commercial breaks more rigorously.
Note that the Loudness Controller operates with reference to an absolute subjective
loudness threshold that does not adapt to program context. This means that if there
is a transition between very quiet program material (like footfalls through rustling
leaves) and a commercial, the commercial may still seem offensively loud even
though the Loudness Controller is controlling its loudness correctly with reference to
other sounds that reach full-scale loudness. Philosophically, this is inevitable; the
Loudness Controller cannot reduce the level of the commercial to the level of rus-
tling leaves without destroying the effectiveness of the commercial and angering
the sponsor!

BS.1770 Safety Limiter

Following the CBS Loudness Controller is a BS.1770 Safety Limiter that will prevent a
BS.1770-2 loudness meter with 10-second integration time from indicating higher
than the setting of the BS.1770 T
panel when the Modify button is pressed. The BS.1770 T
the on-air Processing Preset, so if you change the setting of this control from its de-
fault value (which we recommend doing), you should save your work as a User Pre-
set.
Because some organizations will disqualify an automatic loudness controller if it
causes a BS.1770 meter to read higher than a specified threshold, all of the "TV"
factory presets have this controller active with the BS.1770 T
0 LK. If your organization does not have a strict policy about processing for the
BS.1770 meter, we recommend that you edit your preferred preset by setting this
control anywhere from +2 to O
The total amount of loudness control-induced gain reduction is the sum
of the gain reduction produced by the CBS Loudness Controller and the
gain reduction produced by the BS.1770 safety limiter. The gain reduc-
tion produced by the BS.1770 safety limiter changes slowly, seldom ex-
A
control provides another way to maintain the
OUDNESS TTACK
A
OUDNESS TTACK control (and possibly different settings of the
control as well). Try a slow attack (50% or below) for dramatic
HRESHOLD
and then saving the result as a User Preset.
FF
control, which is available on the front
HRESHOLD
HRESHOLD
OPERATION
control is part of
control set to
3-13