Orban OPTIMOD 6300, Руководство по эксплуатации

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OPERATION ORBAN MODEL 6300
MB GATE (“Multiband Gate Threshold”) control determines the lowest input level
that will be recognized as program by OPTIMOD 6300; lower levels are considered
to be noise or background sounds and cause the AGC or multiband compressor to
gate, effectively freezing gain to prevent noise breathing.
The multiband gate only works appropriately when the K
NEE
and R
ATIO
controls of
all bands are set identically, which is typically the case in broadcast applications. We
recommend turning off the multiband gate if the individual
K
NEE
and
R
ATIO
settings
are unequal.
There are two independent gating circuits in the 6300. The first affects the AGC and
the second affects the multiband compressor. Each has its own threshold control.
The multiband silence gate causes the gain reduction in bands 2 and 3 of the multi-
band compressor to move quickly to the average gain reduction occurring in those
bands when the gate first turns on. This prevents obvious midrange coloration un-
der 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
neighbor), 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, with-
out introducing obvious coloration, the gating smoothly preserves the average
overall frequency response “tilt” of the multiband compressor, broadly maintaining
the “automatic equalization” curve it generates for a given piece of program mate-
rial.
If the
MB GATE
control is turned
O
FF
, the
DJ B
ASS
control (in the Equaliza-
tion screen) is disabled.
DwnExp Thr (“Downward Expander Threshold”) determines the level below which
the single-ended noise reduction system’s downward expander begins to decrease
system gain and below which the high frequencies begin to become low-pass fil-
tered 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 V1.1 software) allows you to fine-tune
the Band 5 downward expander’s threshold by adding or subtracting an offset from
the setting of the
MB D
OWN
E
XPAND
control. Activate the single-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.
Ordinarily, the gating on the AGC and multiband limiter will prevent objectionable
build-up of noise and you will want to use the single-ended noise reduction only on
unusually noisy program material. Modern commercial recordings will almost never
need it. We expect that its main use will be in talk-oriented programming, including
sports.