Orban OPTIMOD-FM 5500 Operation Manual page 156

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OPERATION
M D G R
AXIMUM ELTA AIN
control to some positive number, depending on how much automatic width control
you want the 5500 to perform.
AGC Bass Delta Threshold works the same as AGC M
applies to the bass band. You will usually set it the same as AGC M
T .
HRESHOLD
AGC Crossover allows you to choose A
is a phase-rotating crossover like the one used in the 8200's two-band AGC.
A
LLPASS
It introduces one pole of phase rotation at 200 Hz. 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 fre-
quency. The two bands are down 3 dB at the crossover frequency.
All Five-Band factory presets automatically use A
ing behavior and low delay. Its allpass characteristic complements the existing phase
rotator that reduces voice distortion. Because the Five-Band structure uses phase-
rotating crossovers in the five-band compressor/limiter, there is little or nothing to
be gained by using a phase-linear crossover in the Five-Band structure's AGC.
(Linear-Phase; no delay) is a phase-linear crossover whose upper
L N D
INEAR O ELAY
band is derived by subtracting its lower band from the crossover's input. When the
upper and lower bands have the same gain, their sum is perfectly flat with no phase
rotation. However, when the upper and lower bands have different gains, peaks and
dips appear in the frequency response close to the crossover frequency.
L N D is available in Two-Band presets only. It is useful if you need a cross-
INEAR O ELAY
over 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.
is a phase-linear crossover whose upper band is derived by subtracting its
L
INEAR
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.
is available for Two-Band presets only. While it has the ideal combination of
L
INEAR
no phase distortion (even when non-flat) and smooth shelving behavior, it adds
about 4 ms to the overall delay (compared to A
not a good choice if you need to drive talent headphones.
control to 3.0 and the AGC M
EDUCTION
LLPASS
ORBAN MODEL 5500
ASTER
D
ASTER ELTA
, L , or L
N D
INEAR O ELAY INEAR
because of its smooth, shelv-
LLPASS
and L
N
LLPASS INEAR
D T
ELTA HRESHOLD
T , but
HRESHOLD
D
ASTER ELTA
modes.
), so it is
D
O ELAY