Orban OPTIMOD-AM 9300, Руководство по эксплуатации

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OPTIMOD-AM DIGITAL OPERATION
3-27
than the window size, the
AGC W
INDOW
R
ELEASE
control determines the attack and
release times. This is usually much slower than the normal AGC time constants. This
prevents the AGC from building up density in material whose level is already well
controlled.
The previous explanation was somewhat simplified. In fact, the window has “soft
edges.” Instead of switching abruptly between time constants, the attack and re-
lease times morph smoothly between the setting of the
W
INDOW
R
ELEASE
control and
the setting of the AGC master release and attack controls.
The normal setting for the AGC W
INDOW
S
IZE
is 3dB.
AGC Window Release (see AGC
W
INDOW
S
IZE above.)
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 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 lev-
el, both measured in units of dB.
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 make the idle gain track the setting of the
AGC D
RIVE control, set
the
AGC I
DLE
G
AIN control to zero. To make the idle gain 2 dB lower than the setting
of the
AGC D
RIVE control, set the
AGC I
DLE
G
AIN control to –2.
AGC Bass Attack sets the attack time of the AGC bass compressor (below 200Hz).
AGC Master Attack sets the attack time of the AGC master compressor (above
200Hz).
AGC Bass Release sets the release time of the AGC bass compressor.