Optimod-Surround 8685 V1.0 Operating Manual - Orban

OPTIMOD SURROUND PROCESSOR OPERATION 3-55
is a good starting point for setting this control.
Loudness Controller Attack: See Loudness Control on page 3- 14.
Loudness Controller Bass Couple: See Loudness Control on page 3- 14.
Master Main>Center Max +Delta GR: Along with the other XXX DELTA GR controls,
this control is explained in Multiband , starting on page 3-11.
The Five-Band Structure
The Five-Band structure consists of a stereo enhancer, a slow gain-riding two-band
AGC, an equalization section, a five-band compressor, a dynamic single-ended noise
reduction system, an output mixer (for the five bands), a loudness controller, and a
low-IM look-ahead limiter.
Unlike the Two-Band structure, whose two-band compressor has a continuously
variable release time, the release time of the Five-Band compressor is switchable to
seven increments between slow and fast. Each setting makes a significant difference
in the overall flavor and quality of the sound.
When the input is noisy, you can sometimes reduce the noise by activating the single-ended
noise reduction system. Functionally, the single-ended noise reduction
system combines a broadband downward expander with a program-dependent lowpass
filter. This noise reduction can be valuable in reducing audible hiss, rumble, or
ambient studio noise on-air. We use it for the news and sports factory presets.
Using the Five-Band Structure
The Five-Band structure is very flexible, enabling you to fine-tune your on-air sound
for your target audience and desired market position. There are several basic Factory
Presets for the Five-Band structure. Each of these presets can be edited with the
LESS-MORE control. This control affects the sound-for-picture-oriented presets differently
than it does the music presets (presets with “music” in their names). When a
sound-for-picture-oriented preset is on the air, the LESS-MORE control adjusts the
average amount of gain reduction by adjusting the drive level to the Five-Band
structure's input. This also adjusts the idle gain—the amount of gain reduction in
the AGC section when the structure is gated. (It gates whenever the input level to
the structure is below the threshold of gating.)
When a music preset is on the air, the LESS-MORE control sets the amount of overall
processing, making optimum tradeoffs between loudness, brightness, and distortion.
In sound for picture, there are no loudness wars; for music presets, there is no
need to advance the LESS-MORE control beyond its setting in the Factory Presets.
The five-band compressor/limiter in the Surround structure is always stereo-coupled.
The five-band compressor/limiter in the 2.0 processing can be stereo-coupled to any
extent via the various Bx MAX DELTA GR controls.