Orban OPTIMOD-FM 5500 Operation Manual page 155

OPTIMOD-FM DIGITAL
ratio to as low as 2:1. This can add a sense of dynamic range and is mostly useful for
subtle formats like classical and jazz.
This control reduces the available range of AGC gain reduction because it acts by at-
tenuating the gain control signal produced by the AGC sidechain. The range is 25 dB
at :1 and 12 dB at 2:1. However, the range of input levels that the AGC can handle
is unaffected, remaining at 25 dB.
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
trol affects the sound less and less.
The interaction between the AGC B
trol is a bit complex, so we recommend leaving the AGC B
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
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
setting. The AGC I
gain setting determined by the AGC D
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
the AGC I
G
DLE AIN
of the AGC D
RIVE
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.
AGC Master Delta Threshold allows you to set the difference between the com-
pression thresholds of the sum and difference channels. (This control is only useful
when you set the AGC MATRIX to S
difference channel lower than the sum channel, the AGC will automatically produce
more gain reduction in the difference channel. This will reduce the separation of
material with an excessively wide stereo image (like old Beatles records). To make
this work, you must set the AGC M
zero. For example, to limit an excessively wide image while preventing more than 3
dB difference in gain between the sum and difference channels, set the AGC
control is moved towards "100%," the AGC B
ASS
G control allows you to add or subtract gain from the idle
DLE AIN
RIVE
control to zero. To make the idle gain 2 dB lower than the setting
control, set the AGC I
UM
AXIMUM
control and the AGC B C
T
HRESHOLD
ASS
setting — a setting of 10 dB
RIVE
setting.
G control to –2.
DLE AIN
/ .) If you set the threshold of the
DIFFERENCE
D G R
ELTA AIN EDUCTION
OPERATION
con-
T
ASS HRESHOLD
con-
PL
T control at
HRESHOLD
RIVE
control, set
RIVE
control away from
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