Orban OPTIMOD-FM 8700, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL OPERATION
3-45
L
I
N
O
D
LY
is useful if you need a crossover with low delay and no phase
distortion when flat. Its downside is the possibility of coloration when
the gains of the two bands are widely disparate.
L
INEAR
is a phase-linear crossover whose upper band is derived by subtracting its
lower band from the crossover’s input, as passed through a delay equal to the group
delay of the lowpass crossover filter. The overall frequency response remains smooth
as the two bands take different degrees of gain reduction—the response is a smooth
shelf without extra peaks or dips around the crossover frequency. The two bands are
each down 6 dB at the crossover frequency. This crossover has constant delay even
when the two bands have unequal gains.
While L
INEAR
has the ideal combination of no phase distortion (even
when non-flat) and smooth shelving behavior, it adds about 4 ms to the
overall delay (compared to
A
LLPASS
and
L
I
N
O
D
LY
), so it is not a good
choice if you need to drive talent headphones.
Peak Limiter Controls
There are two sets of peak limiter controls, one of which is active when an 8500-
style preset is active and the other of which is active when an “MX” preset (which
uses the 8700i’s new peak limiter technology) is active. For a given limiter algorithm
(8500-style or “MX”), the peak limiter controls are common to the Two-Band and
Five-Band structures, except as noted in the control descriptions on the following
pages. In the Five-Band structure, the peak limiter is located after bands 1 and 2 are
summed. In the Two-Band structure, the peak limiter is located after the Bass band.
Peak Limiter Controls Common to 8500-style and MX Presets
Except for
C
OMP
M
ODE
and
M
ULTIPLEX
O
FFSET
, which are only available in the Ad-
vanced Modify, all of the peak limiter controls common to 8500-style and MX Presets
appear in both the Intermediate Modify and Advanced Modify screens.
Monitor Drive sets the drive level into the FM peak limiter in the low-delay monitor-
ing processor, which is a separate instance of the Ultra-Low Latency structure. Turn-
ing it up produces more FM peak limiter artifacts in the monitor output. Turning it
down makes the monitor sound cleaner.
Because the ULL structure’s peak limiter has lower performance than the
normal-latency and MX structures, you will not be able to match the
Peak limiter Controls Common to 8500-Style and MX Presets
Intermediate Name Advanced Name Range
(Composite) Limit Drive Comp Drive Off, 0 ... 3 dB
—
PilotProtect Off, On
—
Multiplex Offset
0 … –10 dB
—
Comp Mode
–3.0 … +5.0
--- Monitor Drive
–6. 0… 0.0 dB
Table 3-6: Peak Limiter Controls Common to 8500-Style and MX Presets