Orban OPTIMOD-FM 8600, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL OPERATION
3-53
hear all the music. Then, when the music gets loud, the radio blasts and distorts,
which makes listening unpleasant.
The Two-Band structure is well suited for classical formats during daytime hours
when most people in the audience are likely to be listening in autos or to be using
the station for background music. This audience is best served when the dynamic
range of the program material is reduced by 10-15 dB so that quiet passages in the
music never fade into inaudibility under these less-favorable listening conditions.
OPTIMOD-FM controls the level of the music in ways that are, for all practical pur-
poses, inaudible to the listener. Low-level passages are increased in level by up to 10
dB, while the dynamics of crescendos are maintained.
The
CLASSICAL-2 BAND
and
CLASSIC-2B MX
presets are two-band presets with the
AGC turned off. They use considerable bass coupling to preserve the spectral bal-
ance of the input as well as possible. Their
L
ESS
-M
ORE
controls primarily affect the
amount of compression, not the maximum loudness.
CLASSICAL-2B+AGC
AND
CLASSIC-2B+AGC MX
use the AGC set for 2:1 compression
ratio. Because of the AGC, these presets affect more of the total dynamic range of
the recording that does the
CLASSICAL-2 BAND
preset. However, the AGC provides
extremely smooth and unobtrusive compression because of the gentle ratio and
window gating. In this preset, the Two-Band compressor is used very lightly with a
fast release time as a peak limiter. The AGC does almost all of the compression.
During the evening hours when the audience is more likely to listen critically, a clas-
sical station may wish to switch to a custom preset (derived from the
CLASSIC-2B
MX
or
CLASSICAL-2 BAND
presets) that performs less gain reduction. You can create
such a preset by modifying the
CLASSICAL-2 BAND
preset with the
L
ESS
-M
ORE
con-
trol—turn it down to taste.
There are also four five-band classical presets—two presets and their MX
variants. The MX variants of the
CLASSICAL
presets achieve the lowest
distortion and most open high frequencies. The
CLASSICAL-5 BAND
pre-
set uses the five-band structure with AGC defeated. It uses substantial in-
terband coupling to retain much of the frequency balance of the original
source, but is capable of somewhat more “automatic equalization” than
is
CLASSICAL-2 BAND
. It can therefore re-equalize older program mate-
rial, but there is also more risk that it will cause coloration that might of-
fend the classical purist.
CLASSICAL-5B+AGC,
like its two-band counterpart, uses the AGC set for
2:1 compression ratio.
The five-band structure is not phase-linear, so the
CLASSICAL-5 BAND
preset is likely to have slightly less audible transparency than the
CLASSICAL T
WO
-B
AND
structure.
Customizing the Settings
Each Two-Band Factory Preset has a
L
ESS
-M
ORE
control (located in the Basic Modify
screen) that adjusts on-air loudness.
L
ESS
-M
ORE
simultaneously adjusts all of the pro-
cessing controls to optimize the trade-offs between unwanted side effects as pro-
cessing levels are decreased or increased.