Orban OPTIMOD 6300 Operating Manual page 84

2-30
INSTALLATION
 you have adjusted the 6300's D
norm you are transmitting (step (B)a) below).
The 6300's D
IALNORM
ting in S , which will be overridden by the D
ETUP
tive processing preset if this is not set to G
presets, all factory processing presets are configured to use the global
Dialnorm setting specified in the C
The following steps assume that you are driving the Dolby Digital encoder with
the 6300's Digital Output 1, although either output can be assigned to be the
Dialnorm reference output.
A) If your Dolby Digital encoder is receiving metadata from an upstream source,
you must ensure that the following metadata is set according to the steps be-
low:
a) Set ac3_dynrnge metadata to "0," This forces the AC3 encoder to
reauthor the line-mode DRC metadata, following the encoder's active Line-
Mode level compression profile.
b) Set ac3_compre metadata to "0," This forces the AC3 encoder to reauthor
the RF-mode DRC metadata, following the encoder's active RF-Mode level
compression profile.
B) Navigate to S
ETUP
you press Setup, use the Next button to scroll the display horizontally until
you find it.)
a) Set the D
IALNORM
Dolby Digital metadata you are transmitting to consumers. (Refer to the
manufacturer's instructions for the Dolby Digital encoder you are using for
information on how to set the value of Dialnorm in your transmitted
metadata.)
Most broadcasting organizations have standardized on –23 or –24 dB.
Paragraph H.7 of ATSC Recommended Practice A/85:2011 recommends
–24 LKFS. EBU R128 recommends –23 LUFS. (LKFS and LUFS are the same.
Both are a unit of measure for loudness when the ITU-R BS.1770-2 meter
is used for loudness measurement.)
If you are not driving a Dolby Digital system (in a netcasting application,
for example), follow the recommendations in ATSC A/85 2011a Annex K,
or EBU – TECH 3344.
As you set Dialnorm closer to –11 dB, loudness increases. Eventually, you
will start to see significant limiter gain reduction as the 6300's mastering-
quality look-ahead limiters work harder and harder prevent peak over-
load. Above a certain Dialnorm value, the limiters will start to create au-
dible side effects as they create more and more gain reduction. Allowing
up to 6 dB of limiter gain reduction is usually safe, but the best sounding
limiter gain reduction is no gain reduction at all, so we advise taking ad-
vantage of any available headroom in your transmission channel to
minimize the amount of look-ahead limiter gain reduction.
b) Set the R O
EF UT
IALNORM
value can be set in two places: There is a global set-
ONFIGURATION
> D
IALNORM . (If the Dialnorm page does not appear after
control so it is the same as the Dialnorm value in the
control to DO1.
ORBAN MODEL 6300
R L
EFERENCE EVEL to match the Dial-
setting in the ac-
IALNORM
. Except for the analog TV
LOBAL
tab.