Orban OPTIMOD 6300 Operating Manual page 192

3-50
OPERATION
produce.
The release rate (in dB/second) in the 2-band compressor automatically becomes
faster as more gain reduction occurs. This makes the program progressively denser,
creating a sense of increasing loudness although peaks are not actually increasing.
At the gain reduction values set by the 2B M
B
REAKPOINT controls, the release rate for these bands becomes constant and density
does not increase with additional amounts of gain reduction.
2B REL SHAPE ("2B Release Shape") selects a LINear or EXPonential release shape.
Linear causes the 2-band compressor to release at a constant number of dB per sec-
ond above the 2B B
REAKPOINT
duction otherwise.
Despite its name, E
XPONENTIAL
causes the release to commence slowly and then speed up as it progresses. The
E
XPONENTIAL shape allows you to create the open sound of a slow release time with
program material that is well controlled in level, while permitting the processing to
quickly correct excessively low input levels. We recommend using Exponential for
general-purpose sound-for-picture programming. For program material dominated
by music, L
may be a better choice because Exponential may create unnatural
INEAR
side effects. (If the 2B Release control is set between about 0.5 and 2 dB/second, an
Exponential release shape should cause no problems even with music.)
Note: The B
REAKPOINT
2B GATE ("2B Gate Threshold") threshold control determines the lowest input level
that will be recognized as program material by OPTIMOD 6300; lower levels are con-
sidered to be noise or background sounds and will cause the AGC or 2-band com-
pressor to gate, effectively freezing gain to prevent noise breathing.
There are two independent gating circuits in the 6300 2-band structure. The first af-
fects the AGC and the second affects the 2-band compressor. Each has its own
threshold control.
The 2-band gain reduction will eventually recover to 0 dB (when the
is set to L ) or to the setting of the 2B D
INEAR
set to E
). However, recovery is slow enough to be imperceptible. This avoids
XP
OPTIMOD 6300's getting stuck with a large amount of gain reduction on a long,
low-level musical passage immediately following a loud passage.
In E
release mode, the 2-band gate's gated gain reduction is the same
XP
as the setting of the 2B D
the AGC gate. This is because E
picture processing and is used in the TV 2B G
P +LC presets. In these presets, the AGC is defeated so that all gain
URP
riding can occur in the 2-band compressor. See AGC Idle Gain on page 3-
44 for a more complete discussion.
It is common to set the 2B G
Higher values are useful in sound-for-picture processing to prevent background
setting and proportionally to the amount of gain re-
actually offers a reverse-exponential characteristic: It
controls do nothing when E
RIVE CONTROL
XP
control between approximately –35 dB and –25 dB.
ATE
B
ASTER REAKPOINT
release is chosen.
XPONENTIAL
control (when the
RIVE
, which is similar to the behavior of
release is mainly useful in sound-for-
P and TV 2B G
EN URPOSE
ORBAN MODEL 6300
and 2B B
ASS
S
RELEASE HAPE
S
is
RELEASE HAPE
EN