Orban OPTIMOD-FM 8500S Operating Manual page 205

OPTIMOD-FM DIGITAL
Hard Clip Shape (Hard Clip Shape) allows you to change the knee of the in-
put/output gain curve of the bass clipper when B
lows you to control the shape of the "knee"—the transition between no clipping
and flat-topping. "0" provides the hardest knee, where the transition between lin-
ear operation and flat-topping occurs abruptly as the clipper's input level is
changed. "10" is the softest knee, where the transition starts 6 dB below
setting and occurs gradually. The factory default setting is "7.6."
B C T
ASS LIP HRESH
The M
ahead algorithms that produce lower distortion than H
less of where the H
H
ARD
a tradeoff between punch and bass distortion that is more appropriate
for pop music requiring substantial bass punch to make its musical point.
In any event, the H
sound palette—one that is not duplicated by the existing M
bass clipper characteristics.
This control does nothing if the B
FINAL CLIP ("Final Clip Drive") adjusts the level of the audio driving the back end
clipping system that OPTIMOD-FM uses to control fast peaks. This control primarily
determines the loudness/distortion trade-off.
Turning up the F
INAL
harder, reducing the peak-to-average ratio, and increasing the loudness on the air.
When the amount of clipping is increased, the audible distortion caused by clipping
also increases. Although lower settings of the F
they make the sound cleaner.
If the R control is set to its faster settings, the distortion produced by the
ELEASE
back-end clipping system will increase as the M
The F
C D
INAL LIP RIVE
turned down to compensate. To best understand how to make loudness/distortion
trade-offs, perhaps the wisest thing to do is to recall a factory multiband preset, and
then to adjust the L
each setting of the L
and M L
ULTIBAND IMIT
grammers made the trade-offs between the settings of the various distortion-
determining controls at various levels of processing.
The 8500S's multiband clipping and distortion control system works to
help prevent audible distortion in the final clipper. As factory program-
mers, we prefer to adjust the FINAL CLIP control through a very narrow
range (typically –0.5 dB to –1.0 dB) and to determine almost all of the
loudness/distortion trade-off by the setting of the M
control.
The final clipper operates at 256 kHz sample rate and is fully anti-aliased.
Composite Limit Mode determines if the composite limiter will operate as a hard
clipper or as Orban's patented "Half-Cosine Interpolation" composite limiter (which
is not a clipper).
and S bass clipper characteristics use sophisticated look-
ED OFT
C S
ARD LIP
mode with the H
C
ARD LIP
C S
ARD LIP HAPE
control drives the final clipper and overshoot compensator
C
LIP
and/or the M
ULTIBAND
control to several settings throughout its range. At
-M
ESS ORE
-M control, examine the settings of the M
ESS ORE
T controls. This way, you can see how the factory pro-
HRESHOLD
C M
ASS LIP ODE
control is set. However, operating in
HAPE
control set beyond "0" may produce
S
HAPE
control adds a useful color to the 8500's
is set to M
C M
ASS LIP ODE
control reduce loudness,
C
INAL LIP
D
ULTIBAND RIVE
controls may have to be
L T
IMIT HRESHOLD
OPERATION
is set to HARD. It al-
mode, regard-
ARD
and S
ED OFT
or S .
ED OFT
control is advanced.
D
ULTIBAND RIVE
C
ULTIBAND LIPPING
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