Orban OPTIMOD-FM 8600Si, Руководство по эксплуатации

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OPERATION ORBAN MODEL 8600Si
gate.
When the AGC produces 10 dB of gain reduction, the calibration of the MB GATE
control in V2.x software is the same as it was in V1.x software. When upgrading
from V1.x to V2.x, it should thus be unnecessary to change the MB GATE setting in
User Presets unless the AGC’s nominal gain reduction is significantly different from
10 dB.
The multiband compressor gate causes the gain reduction in bands 2 and 3 of the
multiband compressor to move quickly to the average gain reduction occurring in
those bands when the gate first turns on. This prevents obvious midrange coloration
under gated conditions, because bands 2 and 3 have the same gain.
The gate also independently freezes the gain of the two highest frequency bands
(forcing the gain of the highest frequency band to be identical to its lower neigh-
bor) and independently sets the gain of the lowest frequency band according to the
setting of the
DJ B
ASS
boost control (in the Equalization screen). Thus, without in-
troducing obvious coloration, the gating smoothly preserves the average overall fre-
quency response “tilt” of the multiband compressor, broadly maintaining the “au-
tomatic equalization” curve it generates for a given piece of program material.
Note: If the
MB G
ATE
T
HRESH
(Gate Threshold) control is turned
O
FF
, the
DJ B
ASS control (in the Equalization screen) is disabled.
MB Clipping sets the drive level to the multiband distortion controlling processing
that precedes the final clipping section. The distortion-controlling section uses a
combination of distortion-cancelled clipping and look-ahead processing to antici-
pate and prevent excessive clipping distortion in the final clipper.
Like any other dynamics processing, the distortion-controlling section can produce
artifacts of its own when overdriven. These artifacts can include loss of definition,
smeared high frequencies, a sound similar to excessive compression, and, when op-
erated at extreme settings, audible intermodulation distortion. You can adjust the
MB C
LIPPING
control to prevent such artifacts or to use them for coloration in “highly
processed” formats.
MB Down Expander (Multiband Downward Expander Threshold) determines
the level below which the single-ended noise reduction system’s downward ex-
pander begins to decrease system gain and below which the high frequencies begin
to become low-pass filtered to reduce perceived noise. There are two controls: the
MB D
OWN
E
XPANDER
control sets the expansion threshold in Bands 1-4, while the
B5
D
OWN
E
XPANDER
D
ELTA
T
HRESH
control (first introduced as part of V2.0 software) al-
lows you to fine-tune the Band 5 downward expander’s threshold by adding or sub-
tracting an offset from the setting of the
MB D
OWN
E
XPAND
control. Activate the sin-
gle-ended dynamic noise reduction by setting these controls to a setting other than
O
FF
.
The single-ended noise reduction system combines a broadband downward ex-
pander with a program-dependent low-pass filter. These functions are achieved by
causing extra gain reduction in the multiband compressor. You can see the effect of
this extra gain reduction on the gain reduction meters.