Orban Optimod-PC 1101, Operating Manual

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OPTIMOD-PC OPERATION
3-41
sion of the L–R signal to the original L–R to create stereo enhancement. (See Stereo
Enhancement on page 3-11 for more information.)
It is unwise to use stereo enhancement with low bitrate codecs. At low bitrates,
these codecs use various parametric techniques for encoding the spatial attributes of
the sound field. Stereo enhancement can unnecessarily stress this encoding process.
Both modes have gating that operates under two conditions.
•
The two stereo channels are close to identical in magnitude and phase.
In this case, the enhancer assumes that the program material is actually
mono and thus suppresses enhancement to avoid creating undesired
channel imbalance.
•
The ratio of L–R / L+R of the enhanced signal tries to exceed the threshold set by
the L-R / L+R Ratio Limit control.
In this case, the enhancer prevents further enhancement in order to pre-
vent excess L–R energy, which can increase multipath distortion.
The stereo enhancer has the following controls:
Amount sets the maximum spatial enhancement.
Enhancer In / Out bypasses the stereo enhancer. O
UT
is equivalent to setting the
A
MOUNT
to 0.
L-R / L+R Ratio Limit sets the maximum amount of enhancement to prevent multi-
path distortion. However, if the original program material exceeds this limit with no
enhancement, the enhancer will not reduce it.
Diffusion applies only to the D
ELAY
enhancer. This control determines the amount
of delayed L–R added to the original signal.
Style sets one of two stereo enhancer types: 222 or D
ELAY
.
Depth sets the delay in the delay line. It applies only to the
D
ELAY
enhancer.
AGC Controls
The AGC is common to the Two-Band and Five-Band structures.
Five of the AGC controls are common to the Full Modify and Advanced Modify
screens, with additional AGC controls available in the Advance Modify screen, as
noted in the following table.
These controls are explained in detail below.
Each Factory Preset has a
L
ESS
-M
ORE
control that adjusts loudness by altering the
amount of dynamics processing.
L
ESS
-M
ORE
simultaneously adjusts several of the