Orban OPTIMOD-FM 8600Si, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL OPERATION
3-9
Two-Band Gated AGC: The AGC is a two-band device, using Orban’s patented
“master / bass” band coupling. It has an additional important feature: target-zone
gating. If the input program material’s level falls within a user-settable window (typ-
ically 3 dB), then the release time slows to a user-determined level. It can be slow
enough (0.5 dB/second) to effectively freeze the operation of the AGC. This prevents
the AGC from applying additional, audible gain control to material that is already
well controlled. It also lets you run the AGC with fast release times without adding
excessive density to material that is already dense.
The AGC contains a compression ratio control that allows you to vary to ratio be-
tween 2:1 and essentially
∞
:1. Lower ratios can make gain riding subtler on critical
formats like classical and jazz.
The AGC has its own silence-gating detector whose threshold can be set independ-
ently of the silence gating applied to the multiband compressor.
Equalization: The 8600Si has steep-slope bass shelving equalizer and three bands
of fully parametric bell-shaped EQ.
You can set the slope of the bass shelving EQ to 6, 12, or 18 dB/octave and adjust the
shelving frequency.
The 8600Si’s bass, midrange, and high frequency parametric equalizers have curves
that were modeled on the curves of Orban’s classic analog parametrics (like the
622B), using a sophisticated, proprietary optimization program. The curves are
matched to better than 0.15 dB. This means that their sound is very close to the
sound of an Orban analog parametric. They also use very high quality filter algo-
rithms to ensure low noise and distortion.
The 8600Si HF Enhancer is a program-controlled HF shelving equalizer. It intelli-
gently and continuously analyzes the ratio between broadband and HF energy in
the input program material and can equalize excessively dull material without over-
enhancing bright material. It interacts synergistically with the five-band compressor
to produce sound that is bright and present without being excessively shrill.
Multiband Compression: The multiband compressor/limiter can be operated in
five-band or two-band mode. The 8600Si controls high frequencies with distortion-
canceled clipping and, in all but 5-band MX presets, with a high frequency limiter as
well. The clipper operates at 256 kHz-sample rate and is full anti-aliased.
Ordinarily, the gain reduction in band 5 is slaved to the gain reduction in band 4 (as
determined by the setting of the
B4 > B5 C
OUPLE control); these bands are only in-
dependent from the viewpoint of the downward expander and multiband clippers.
However, a high frequency limiter causes additional gain reduction in band 5 when
band 5 multiband clipping alone would be insufficient to prevent HF distortion. The
HF limiter uses a sophisticated analysis of the signal conditions in the 8600Si’s clip-
ping system to do this.
Except in MX presets, a clipper, embedded in the crossover, protects bands 1 and 2
from transient overshoot. This clipper has a shape control, allowing you to vary the
“knee” of its input/output transfer curve from hard (0) to soft (10). Instead of a clip-