Orban OPTIMOD-PC 1100, Руководство по эксплуатации

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OPERATION ORBAN MODEL 1100
ble unless you want the AGC to provide some gentle automatic re-equalization of
the input material.
With the AGC M
ASTER
R
ELEASE
control set to 2 dB/second, setting the AGC B C
PL
control toward 0% (independent) will produce a sound that is very 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, but may pump up
rumble and other noise.
AGC Window Size determines the size of the “target zone” window in the AGC. If
the input level falls within this target zone, the AGC release time is set to the num-
ber specified by the AGC
W
INDOW
R
ELEASE
control. This is usually much slower than
the normal AGC release; it essentially freezes the AGC gain. This prevents the AGC
from building up density in material whose level is already well controlled. If the
level goes outside the window, then the AGC switches to the release rate specified
by
AGC M
ASTER
R
ELEASE
so the AGC can still correct large gain variations quickly.
The normal setting for the AGC W
INDOW
S
IZE
is 3dB.
AGC Window Release (see AGC W
INDOW
S
IZE
above.)
AGC Ratio determines the compression ratio of the AGC. The compression ratio is
the ratio between the change in input level and the resulting change in output
level, both measured in units of dB.
OPTIMOD-PC compressor can be operated at a compression ratio as low as 2:1. This
can add a sense of dynamic range and is mostly useful for subtle fine arts formats
like classical and jazz.
AGC Bass Threshold determines the compression threshold of the bass band in the
AGC. It can be used to set the target spectral balance of the AGC.
As the
AGC B C
PL
control is moved towards “100%,” the
AGC B
ASS
T
HRESHOLD
con-
trol affects the sound less and less.
The interaction between the AGC B
ASS
T
HRESHOLD
control and the AGC B C
PL
con-
trol is a bit complex, so we recommend leaving the
AGC B
ASS
T
HRESHOLD
control at
its factory setting unless you have a good reason for readjusting it.
AGC Idle Gain . The “idle gain” is the target gain of the AGC when the silence gate
is active. Whenever the silence gate turns on, the gain of the AGC slowly moves to-
wards the idle gain.
The idle gain is primarily determined by the AGC D
RIVE
setting—a setting of 10 dB
will ordinarily produce an idle gain of –10 dB (i.e., 10 dB of gain reduction). How-
ever, sometimes you may not want the idle gain to be the same as the
AGC D
RIVE
setting. The
AGC I
DLE
G
AIN
control allows you to add or subtract gain from the idle
gain setting determined by the AGC D
RIVE
setting.
You might want to do this if you make a custom preset that otherwise causes the
gain to increase or decrease unnaturally when the AGC is gated. For example, to