Orban OPTIMOD-AM 9300, Руководство по эксплуатации

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OPTIMOD-AM DIGITAL OPERATION
3-35
graphic equalizer to fine-tune the spectral balance of the program material over a

3 dB range.
Their range has been purposely limited because the only gain control element after
these controls is the back-end clipping system (including the final clipper and over-
shoot compensator), which can produce considerable audible distortion if over-
driven. We have carefully tuned the thresholds of the individual compressors to pre-
vent audible distortion with almost any program material. Large changes in the fre-
quency balance of the compressor outputs will change this tuning, leaving the 9300
more vulnerable to unexpected audible distortion with certain program material.
Because all these controls are located
before the compressor, you should make large
changes in EQ with the bass and parametric equalizers, the HF enhancer, and the in-
dividual band drive controls. The compressors will protect the system from unusual
overloads caused the chosen equalization. Use the output mix controls only for fine-
tuning and spend time with a variety of program material to make sure that your
adjustments have not caused excessive clipping distortion.
You can also get a similar effect by adjusting the compression threshold
of the individual bands. This is comparably risky with reference to clipper
overload, but unlike the
MB B
AND
M
IX
controls, does not affect the fre-
quency response when a given band is below threshold and is thus pro-
ducing no gain reduction.
B1-B5 On/Off switches allow you to listen to any band (or any combination of
bands) independently. This is a feature designed for intermediate or advanced users
and developers when they are creating new 9300 presets.
Please note that a single band will interact with the back-end clipping system quite
differently than will that band when combined with all of the other bands. There-
fore, do not assume that you can tune each band independently and have it sound
the same when the clipping system is processing all bands simultaneously.
B1-B5 Attack (Time) controls set the speed with which the gain reduction in each
band responds to level changes at the input to a given band’s compressor. These
controls are risky and difficult to adjust appropriately. They affect the sound of the
processor in many subtle ways. The main trade-off is “punch” (achieved with slower
attack times) versus distortion (because slower attack times increase overshoots that
must be eliminated in the clipping system). The results are strongly program-
dependent and must be verified with listening tests to a wide variety of program
material.
The
A
TTACK time controls are calibrated in arbitrary units. Higher numbers corre-
spond to slower attacks.
Delta Release controls are differential controls. They allow you to vary the release
time in any band of the Five-Band compressor/limiter by setting an offset between
the
M
ULTIBAND
R
ELEASE setting and the actual release time you achieve in a given
band. For example, if you set the
M
ULTIBAND
R
ELEASE control to medium-fast and the
B
AND
3 D
ELTA
GR
control to –2, then the band 3 release time will be the same as if
you had set the
M
ULTIBAND
R
ELEASE control to medium and set the
B
AND
3 D
ELTA
GR
control to 0. Thus, your settings automatically track any changes you make in the