Grass Valley 2020ADC A-To-D User Manual
Page 22
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2020ADC — Instruction Manual
Configuration
This display also provides gain adjustment to set the maximum signal level
(MSL) of the analog inputs for full-scale digital outputs (0 dBFS). For an
overview of how to adjust the gain, refer to
Adjust the gain in either
NUMERIC
or
SLIDERS
mode as shown in
•
In
NUMERIC
mode, the single arrows increment the numeric display
value by 0.1 dB and the double arrow increments the value by 1.0 dB
(10x).
•
In
SLIDERS
mode, the gain range is distributed over the bar display
which is divided into approximately 256 steps. The single arrow will
increment the resulting value by 1x and the double arrow will incre-
ment by 10x. The returned bar position will be an approximate
(rounded off) value.
Note
In NUMERIC mode only, values selected with the single or double arrow keys
will be enabled immediately. All other display entries, including typed in
values, require pressing APPLY before the selection is enabled.
This module has been set up at the factory with a maximum signal level
(MSL) default value of +24 dBu = 0 dBFS. The remote controls will allow a
gain adjustment range from -4 dB to +12 dB. The MSL can vary from
+28 dBu to +12 dBu.
•
If you know your input MSL, you can enter a value into the display to
make it equal to +24 dBu. For example, if you know your MSL is
+24 dBU, enter 0 into the display. If your MSL is +28 dBu, enter -4 to
bring it to the +24 default. If it is a lower value, such as +18, enter +6 to
bring it up to the default value.
•
If you don’t know your exact maximum signal level, you may use the
display >-20 dBFS and Clip status items to approximate the proper
levels.
Adjust the gain of each channel in the display until the maximum signal level
is clipping (
CH 1 L CH >0.5 DB
and
CH 2 R CH >0.5 DBFS CLIP
values read
TRUE
).
Then lower the gain just until the Clip values change to
FALSE
and the
>-20 dBFS values for Ch 1/Ch 2 read
TRUE
.