Orban OPTIMOD-FM 8500S Operating Manual page 213

OPTIMOD-FM DIGITAL
The two-band gain reduction will eventually recover to 0 dB and the AGC gain re-
duction will eventually recover to –10 dB even when their compressor gates are
gated. However, recovery is slow enough to be imperceptible. This avoids OPTIMOD-
FM's getting stuck with a large amount of gain reduction on a long, low-level musi-
cal passage immediately following a loud passage.
It is common to set the 2B G
useful for radio drama, outside sports broadcasts, and other non-musical program-
ming that contain ambiance, low-level crowd noise, and the like. Slightly higher set-
tings may increase the musicality of the compression by slowing down recovery on
moderate-level to low-level musical passages. When such passages cause the gate to
cycle on and off, recovery time will be slowed down by the ratio of the "on-time" to
the "off time." This effectively slows down the release time as the input gets pro-
gressively quieter, thus preserving musical values in material with wide dynamic
range (classical music for example).
2B Bass Coupling control is used to set the balance between bass and the rest of
the frequency spectrum.
The two-band compressor processes audio in a master band for all audio above ap-
proximately 200 Hz and a bass band for audio below approximately 200 Hz. The 2B
control determines how closely the on-air balance of material below
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200 Hz matches that of the program material above 200 Hz.
Settings toward 100% (wideband) make the output sound most like the input. Be-
cause setting the 2B B
the most accurate frequency balance will often be obtained with this control set be-
tween 70% and 90%. The optimum setting depends on the amount of gain reduc-
tion applied. Adjust the 2B B
Reduction meters track as closely as possible.
With the 2B R
ELEASE
control toward 0% (independent) will produce a sound that is very
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open, natural, and non-fatiguing, even with large amounts of gain reduction. Such
settings will provide a bass boost on some program material that lacks bass.
With fast release times, settings of the 2B B
do not sound good. Instead, set the 2B B
pendent). This combination of fast release and independent operation of the bands
provides the maximum loudness and density on small radios achievable by the Two-
Band structure. But such processing may fatigue listeners with high-quality receivers
and also requires you to activate the AGC to control the average drive level into the
two-band compressor, preventing uncontrolled build-up of program density. Instead
of operating the Two-Band structure like this, you should usually choose a Five-Band
preset instead.
2B Master Comp Threshold sets the level where gain reduction starts to occur in
the Master (above 200 Hz) band of the Two-Band Compressor.
T control to –40. Higher settings are primarily
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control at 100% will sometimes cause bass loss,
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(Two-Band Release) control set to 2 dB / second, setting the 2B
control until the band 1 and band 2 Gain
toward 100% (wideband)
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C control toward 0% (inde-
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OPERATION