Optimod-AM 9400 V1.2 Operating Manual - Orban

OPTIMOD-AM DIGITAL OPERATION 3-47
band compressor, and therefore determines the average amount of gain reduction
in the multiband compressor. Range is 25dB.
Adjust the MULTIBAND DRIVE control to your taste and format requirements. Used
lightly with slower multiband release times, the multiband compressor produces an
open, re-equalized sound. The multiband compressor can increase audio density
when operated at faster release times because it acts increasingly like a fast limiter
(not a compressor) as the release time is shortened. With faster release times, density
also increases when you increase the drive level into the multiband compressor
because these faster release times produce more limiting. Increasing density can
make sounds seem louder, but can also result in an unattractive busier, flatter, or
denser sound. It is very important to be aware of the many negative subjective side
effects of excessive density when setting controls that affect the density of the processed
sound.
The MULTIBAND DRIVE interacts with the MULTIBAND RELEASE setting. With slower release
time settings, increasing the MULTIBAND DRIVE control scarcely affects density.
Instead, the primary danger is that excessive drive will cause noise to increase excessively
when the program material becomes quiet.
You can minimize this effect by carefully setting the MULTIBAND GATE THRESHOLD control
to “freeze” the gain when the input gets quiet and/or by activating the singleended
noise reduction.
When the release time of the multiband compressor is set to its faster settings, the
setting of the MULTIBAND DRIVE control becomes much more critical to sound quality
because density increases as the control is turned up. Listen carefully as you adjust it.
With these fast release times, there is a point beyond which increasing multiband
compressor drive will no longer yield more loudness, and will simply degrade the
punch and definition of the sound.
We recommend no more than 10 dB gain reduction as shown on the meters
for band 3. More than 10dB, particularly with the FAST release time,
will often create a “wall of sound” effect that many find fatiguing.
MB REL (“Multiband Release”) control can be switched to any one of seven settings.
Note that the subjective effect of these settings are different in analog AM and HD
listening. To minimize codec artifacts (by avoiding density build-up), it is wise to use
slower MB REL settings in the HD chain. Meanwhile, faster settings in the AM analog
chain will increase program density, helping overcome interference.
The Slow (SLOW and SLOW2) settings produce a very punchy, clean,
open sound that is ideal for Adult Contemporary, Soft Rock, Soft Urban,
New Age, and other adult-oriented formats whose success depends on
attracting and holding audiences for very long periods of time. The
SLOW and SLOW2 settings produce an unprocessed sound with a nice
sense of dynamic range. With these settings, the 9400 processing provides
gentle automatic equalization to keep the frequency balance consistent
from record to record (especially those recorded in different eras).
And for background music formats, these settings ensure that your sound
doesn’t lose its highs and lows.