Orban OPTIMOD 6300 Operating Manual page 151

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OPTIMOD 6300 DIGITAL OPERATION
Stereo Enhancement: The 6300 provides two different stereo enhancement algo-
rithms. The first, called L–R D
ELAY , is based on Orban's patented analog 222 Stereo
Enhancer, which increases the energy in the stereo difference signal (L–R) whenever
a transient is detected in the stereo sum signal (L+R). By operating only on tran-
sients, the 222 increases width, brightness, and punch without unnaturally increas-
ing reverb (which is usually predominantly in the L–R channel).
Gating circuitry detects "mono" material with slight channel or phase imbalances
and suppresses enhancement so this built-in imbalance is not exaggerated. It also
allows you to set a "width limit" to prevent over-enhancement of material with sig-
nificant stereo content, and will always limit the ratio of L–R / L+R to unity or less.
The second stereo enhancement algorithm is based on the well-known "Max" tech-
nique. This passes the L–R signal through a delay line and adds this decorrelated sig-
nal to the unenhanced L–R signal. Gating circuitry similar to that used in the "222-
style" algorithm prevents over-enhancement and undesired enhancement on
slightly unbalanced mono material.
2-band Gated AGC: The AGC is a 2-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 (typically
3dB), 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 exces-
sive 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 6300 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 6300'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 0.15dB. 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 6300 HF Enhancer is a program-controlled HF shelving equalizer that intelli-
gently and continuously analyzes the ratio between broadband and HF energy in
the input program material. It can equalize excessively dull material without over-