OPTIMOD-PC
OPERATION
3-45
reduction system, an output mixer (for the five bands), 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 sin-
gle-ended noise reduction system. Functionally, the single-ended noise reduction
system combines a broadband downward expander with a program-dependent low-
pass filter. This noise reduction can be valuable in reducing audible hiss, rumble, or
ambient studio noise. We use it for the news and sports factory presets.
The Five-Band structure does not have a separate Loudness Controller because its
Five-Band compressor automatically re-equalizes the spectral balance of various
pieces of program material in a way that tends to make their loudness more consis-
tent.
Putting the Five-Band Structure on the Air
The Five-Band structure is very flexible, enabling you to fine-tune your 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
L
ESS
-M
ORE
control. This control affects the video-oriented presets differently than it
does the music presets (presets with “music” in their names). When a video-oriented
preset is on the air, the
L
ESS
-M
ORE
control adjusts the average amount of gain re-
duction by adjusting the drive level to the Five-Band structure's input. This also ad-
justs 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
L
ESS
-M
ORE
control sets the amount of overall
processing, making optimum tradeoffs between loudness, brightness, and distor-
tion. In sound for picture, there are no loudness wars; for music presets, there is no
need to advance the
L
ESS
-M
ORE
control beyond its setting in the Factory Presets.
Customizing the Settings
The controls in the Five-Band structure give you the flexibility to customize your sta-
tion sound. However, as with any audio processing system, proper adjustment of
these controls requires proper balancing of the trade-offs explained above. The fol-
lowing provides the information you need to adjust the Five-Band structure controls
to suit your programming and taste.
