Orban OPTIMOD-AM 9300, Operating Manual

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OPTIMOD-AM DIGITAL OPERATION
3-29
amount of clipping. 0dB refers to the average setting that we have found to be the
best compromise for many settings of the other controls.
If the
MB R
ELEASE
control is set to
FAST
or
MFAST
(medium-fast), perceived clipping
distortion will increase as the
MB D
RIVE
control is advanced, and the
MB C
LIP
control
may have to be turned down to compensate. To best understand how to make
loudness/distortion trade-offs, perhaps the wisest thing to do is to recall a factory
preset and then to adjust the
L
ESS
-M
ORE
control to several settings throughout its
range. At each setting of the
L
ESS
-M
ORE
control, examine the settings of the
MB
D
RIVE
control, the
MB C
LIP
control, and the
F
INAL
C
LIP
drive control. This way, you
can see how the factory programmers made the trade-offs between the settings of
the various distortion-determining controls at various levels of processing.
HF Clipping determines the amount of protection provided by the 9300’s Band 5
multiband clipper. “0” is the preferred setting. Higher values will increase both
brightness and high frequency distortion. This control is for audio processing experts
only; it is important to listen to a very wide range of program material before decid-
ing to set this control above
0
. When the control is set above
0
, there will definitely
be some program material that sounds harsh and distorted, so you must decide if
the trade-off against brighter sound and more vocal presence is acceptable to your
taste.
Final Clip (“Final Clip Drive”) adjusts the level of the audio driving the back end
clipping system that OPTIMOD-AM uses to control fast peaks. This control primarily
determines the loudness/distortion trade-off.
Turning up the
F
INAL
C
LIP control drives the final clipper and overshoot compensator
harder, reducing the peak-to-average ratio, and increasing the loudness on the air.
When the amount of clipping is increased, the audible distortion caused by clipping
also increases. Although lower settings of the
F
INAL
C
LIP control reduce loudness,
they make the sound cleaner.
If the
R
ELEASE control is set to its faster settings, the distortion produced by the
back-end clipping system will increase as the
M
ULTIBAND
D
RIVE control is advanced.
The
F
INAL
C
LIP
D
RIVE and/or the
M
ULTIBAND
L
IMIT
T
HRESHOLD controls may have to be
turned down to compensate. To best understand how to make loudness/distortion
trade-offs, perhaps the wisest thing to do is to recall a factory multiband preset, and
then to adjust the
L
ESS
-M
ORE control to several settings throughout its range. At
each setting of the
L
ESS
-M
ORE control, examine the settings of the
M
ULTIBAND
D
RIVE
and
M
ULTIBAND
L
IMIT
T
HRESHOLD controls. This way, you can see how the factory pro-
grammers made the trade-offs between the settings of the various distortion-
determining controls at various levels of processing.
The 9300’s multiband clipping and distortion control system works to
help prevent audible distortion in the final clipper. As factory program-
mers, we prefer to adjust the FINAL CLIP
control through a very narrow
range and to determine almost all of the loudness/distortion trade-off by
the setting of the Multiband Clipping control.