Orban OPTIMOD-FM 8600, Руководство по эксплуатации

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OPERATION ORBAN MODEL 8600
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 8600’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.
Composite Limit Mode determines if the composite limiter will operate as a hard
clipper or as Orban’s patented “Half-Cosine Interpolation” composite limiter (which
is not a clipper).
When operating as a hard clipper, the composite limiter will produce
maximum brightness in the frequency range from 5 to 15 kHz because,
unlike the 8600’s left/right audio-domain peak limiters, it can produce
square waves in this frequency range. The downside compared to Half-
Cosine mode is that it can noticeably compromise stereo imaging.
When operating in Half-Cosine mode, the composite limiter produces
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
Table 3-5: Peak Limiter Controls Common to 8500-Style and MX Presets