Orban OPTIMOD 6200, Руководство по эксплуатации

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OPERATION ORBAN Model 6200
usually noisy program material. Modern commercial recordings will almost never need
it. We expect that its main use will be in talk-oriented programming, including sports.
Please note that it is impossible to design such a system to handle all program material
without audible side effects. You will get best results if you set the
DWNEXP THR
con-
trol of the noise reduction system to complement the program material you are process-
ing. The
DWNEXP THR
should be set higher when the input is noisy and lower when the
input is relatively quiet. The best way to adjust the
DWNEXP THR
control is to start with
the control set very high. Reduce the control setting while watching the gain reduction
meters. Eventually, you will see the gain increase in sync with the program. Go further
until you begin to hear noise modulation — a puffing or breathing sound (the input
noise) in sync with the input program material. Set the
DWNEXP THR
control higher
until you can no longer hear the noise modulation. This is the best setting.
Obviously the correct setting will be different for a sporting event than for classical mu-
sic. It may be wise to define several presets with different settings of the
DWNEXP THR
control, and to recall the preset that complements the program material of the moment.
Note also that it is virtually impossible to achieve undetectable dynamic noise reduction
of program material that is extremely noisy to begin with, because the program never
masks the noise. It is probably wiser to defeat the dynamic noise reduction with this sort
of material (traffic reports from helicopters and the like) to avoid objectionable side ef-
fects. You must let your ears guide you.
FINAL LIMT (Final Limit) control adjusts the level of the audio driving the look-
ahead limiter OPTIMOD-DAB uses to control fast peaks, and then adjusts the peak-to-
average ratio. The loudness/distortion trade-off is primarily determined by the
FINAL
LIMT
control.
Turning up the
FINAL LIMT
control drives the look-ahead limiter harder, reducing the
peak-to-average ratio, and increasing the loudness on the air. When the amount of limit-
ing is increased, the audible intermodulation distortion caused by limiting is increased.
Lower settings reduce loudness, of course, but result in a cleaner sound.
If the
MB REL
control is set to
fast
or
mfast
(medium-fast), intermodulation distortion in
the look-ahead limiter will increase as the MB DRIVE control is advanced, and the FINAL
LIMT
it 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
multi-band preset, and then to adjust the
LESS-MORE
control to several settings
throughout its range. At each setting of the
LESS-MORE
control, examine the settings of
the MB DRIVE control, the FINAL LIMT control, and the FINAL CLIPPING DRIVE con-
trol. (You can see them by calling up the Full Control screen by pressing the
FULL
CONTROL soft key.) 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.