A Note About Gain Reduction Metering; Excessive Commercial Loudness - Orban 8182A Operating Manual

louder than
another, television has
been
spared
the "loudness
wars"
that
plague
radio
audio
quality.)
There
is
a point
beyond which
increasing density (with
settings
of
the
release
time
control
between 0 and
3)
will
simply degrade
the
punch
and
definition
of
the sound.
And when
OPTIMOD-TV
is
operated with release
time
control
settings
between 0
and
3,
the sound
will
change
substantially
with
the
amount
of
gain reduction. This
means
that
operator gain
riding
is
more
critical
—
you must
decide
on
the basis
of
listening
tests
how much
gain reduction gives you
the dense sound
you want
without
a
feeling
of overcompression and
fatigue.
One
of
two
release shapes can be
selected:
either a constant, linear release
rate,
or
an
exponentially increasing
rate that automatically
becomes
faster as the release
process proceeds.
The
exponential
release
shape
is
most
useful for general
program-
ming, because most
gain
riding
remains slow and
unobtrusive, with only
large gain
corrections
producing
fast
(and therefore
more
audible)
release.
For programming
in
which
the levels
of the input material
are
uniformly
well-controlled the
linear release
shape
gives a
somewhat
smoother
sound.
(We recommend
the exponential shape
for
fine arts
programming
because such
programming
typically includes a variety of
material
in
addition
to,
say,
concerts with
good
level control.)
A
note
about gain
reduction metering.
Unlike
the metering
on some
processors, the
red zone on
the
OPTIMOD-TV
gain
reduction meter's scale
is
a
warning
that
must be
observed.
When
the
meter
is
in
the
red,
it
means
that the
compressor
has
run out of gain
reduction range,
that the
circuitry
is
being
overloaded,
and
that various nastinesses
are likely to
commence.
Because
the
compressor
has a gain reduction range of 25dB,
the
meter
should never
enter the red
zone
if
OPTIMOD-TV
has
been
set
up
for
a sane
amount
of
gain
reduction
under
ordinary
program
conditions.
But be aware of
the different peak
factors
on
voice
and music
—
if
voice
and music
are
peaked
identically
on
a
VU
meter
at
the switcher,
voice
may
cause
up
to
lOdB more
peak gain reduction than
does music! (A
PPM
will indicate relative peak
levels
much
more
accurately.)
When
the gating function
is
activated, the
gain slowly
drifts
toward
lOdB
gain
re-
ductioa Because
the gain reduction meters
will therefore
sit at
lOdB
gain reduction
in
absence of
signal,
we
have
calibrated the
total
master
g/r,
compression master
g/r,
and total BASS
G/R meters
so that
0
corresponds
to
lOdB
gain reduction (and
+ 10
indicates
no
gain reduction)
to
avoid confusing operators
who
might
otherwise
think
that the
compressors were
faulty.
Excessive
commercial
loudness.
The
loudness
controller in the 8
182
A
will
control the loudness of
most
commercials
sufficiently
well
to
eliminate
viewer annoyance. (The
basic
OPTIMOD-TV
processing
by
itself
controls
loudness well enough
that
the loudness
controller
has
no
effect
on
most program
material,
and
will tend
to
cause
additional
gain reduction of only
2-3dB
on
the
most
extreme
material.)
Loudness
is
subjective.
How
loud something sounds does not
correlate well
with
VU
meter
or
PPM
measurements
of
signal
level.
This
is
because:
1)
the absolute levels
of
some
frequency bands
are
more
important than others
in
determining
how
loud
a
sound seems
to
the
listener,
2) a
sound spread out over
a
wide frequency range
5-9