Orban OPTIMOD-FM 8600, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL OPERATION
3-55
with 0-10 dB of gain reduction (with the gain riding
AGC
set to
O
FF
) maintains a
sense of dynamic range while still controlling levels effectively. Because OPTIMOD-
FM’s density gently increases between 0 and 10 dB of compression, 10 dB of com-
pression sounds very natural, even on classical music.
2B Release control determines how fast the two-band compressor releases (and
therefore how quickly loudness increases) when the level of the program material
decreases. This release time only applies when the Two-Band Compressor is not gat-
ed by the silence gate.
The release time can be adjusted from 0.5 dB / second (slow) to 20 dB / second (fast).
Settings toward 20 dB / second result in a more consistently loud output, while set-
tings toward 0.5 dB / second allow a wider variation of dynamic range. Both the set-
ting of the
2B R
ELEASE
control and the dynamics and level of the program material
determine the actual release time of the compressor.
The action of the
2B R
ELEASE
control has been optimized for resolution and adjusta-
bility. However, its setting is critical to sound quality—listen carefully as you adjust it.
There is a point beyond which increasing density (with faster settings of the
2B
R
ELEASE
control) will no longer yield more loudness and will simply degrade the
punch and definition of the sound.
When the
2B R
ELEASE
control is set between 8 and 1 dB / second (the slowest set-
tings), the amount of gain reduction is surprisingly non-critical. Gating prevents
noise from being brought up during short pauses and pumping does not occur at
high levels of gain reduction. Therefore, the primary danger of using large amounts
of gain reduction is that the level of quiet passages in input material with wide dy-
namic range may eventually be increased unnaturally. Accordingly, when you oper-
ate the
2B R
ELEASE
control between 8 and 2 dB / second, it may be wise to defeat
the gain-riding AGC and to permit the two-band compressor to perform all of the
gain riding. This will prevent excessive reduction of dynamic range and will produce
the most natural sound achievable from the Two-Band structures.
With faster
2B R
ELEASE
control settings (above 8 dB / second), the sound will change
substantially with the amount of gain reduction in the two-band compressor. This
means that you should activate the gain-riding AGC to ensure that the two-band
compressor is always being driven at the level that produces the desired amount of
gain reduction. Decide based on listening tests how much gain reduction gives you
the density that you prefer while not creating a feeling of over-compression and fa-
tigue.
Release in the two-band compressor automatically becomes faster as
more gain reduction is applied (up to about 10 dB). This makes the pro-
gram progressively denser, creating a sense of increasing loudness alt-
hough peaks are not actually increasing. If the gain-riding AGC is defeat-
ed (with the
AGC
on/off control), you can use this characteristic to pre-
serve some feeling of dynamic range. Once 10 dB of gain reduction is ex-
ceeded, full loudness is achieved—no further increase in short-term den-
sity occurs as more gain reduction is applied. This avoids the unnatural,
fatiguing sound often produced by processors at high gain reduction lev-
els and makes OPTIMOD-FM remarkably resistant to operator gain-riding
errors.