Orban Optimod-PC 1101, Operating Manual

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OPERATION ORBAN MODEL 1101
AGC, Equalizer, Stereo Enhancer, and Clipper controls are common to both Two-
Band and Five-Band structures and are described in the pages above.
Some of the Two-Band controls are common to the Full Modify and Advanced Mod-
ify screens, with additional Two-Band controls available in the Advanced Modify
screen.
2B DRIVE control adjusts signal level going into the two-band compressor, and
therefore controls the density of output audio by determining the amount of gain
reduction in the two-band compressor. The resulting sound texture can be open and
transparent, solid and dense, or somewhere in between. The range is 0 to 25dB.
Regardless of the release time setting, we feel that the optimal amount of gain re-
duction in the two-band compressor for popular music and talk formats is 10-15dB.
If less gain reduction is used, loudness can be lost. For classical formats, operating
with 0-10 dB of gain reduction (with the gain riding
AGC
set to
O
FF
) maintains a
sense of dynamic range while still controlling levels effectively. Because OPTIMOD-
PC’s density gently increases between 0 and 10 dB of compression, 10 dB of com-
pression sounds very natural, even on classical music.
2B REL (“2B Release”) control determines how fast the two-band compressor re-
leases (and therefore how quickly loudness increases) when the level of the program
material decreases. This release time only applies when the silence gate does not
gate the Two-Band Compressor.
The control can be adjusted from 0.5 dB/second (slow) to 20 dB/second (fast). Set-
tings toward 20 dB/second result in a more consistently loud output, while settings
toward 0.5 dB/second allow a wider variation of dynamic range. Both the setting of
the
2B R
EL
control and the dynamics and level of the program material determine
the actual release time of the compressor. In general, you should use faster release
times for mass-appeal pop or rock formats oriented toward younger audiences, and
slower release times for more conservative, adult-oriented formats (particularly if
women are an important part of your target audience).
We expect that the Two-Band structure will be rarely used for pop music
formats because the Five-Band structure gives better results in almost all
cases.
The action of the 2B R
EL
control has been optimized for resolution and adjustability.
Its setting is critical to sound quality—listen carefully as you adjust it. There is a point
beyond which increasing density (with faster settings of the
2B R
EL
control) will no
longer yield more loudness, and will simply degrade the punch and definition of the
sound.
When the 2B R
EL
control is set between 8 and 0.5 dB/second (slower settings), the
amount of gain reduction is surprisingly non-critical. Gating prevents noise from be-
ing brought up during short pauses and pumping does not occur at high levels of
gain reduction. Therefore, the primary danger of using large amounts of gain reduc-
tion is that the level of quiet passages in input material with wide dynamic range
may eventually be increased unnaturally. Accordingly, when you operate the
2B R
EL
control between 8 and 0.5 dB/second, it may be wise to defeat the gain-riding AGC