Orban OPTIMOD-FM 8700, Operating Manual

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OPTIMOD-FM DIGITAL OPERATION
3-33
The curves in the 8700i’s equalizer were created by a so-called “minimax”
(Minimize the Maximum error, or “equal-ripple”) IIR digital approxima-
tion to the curves provided by the Orban 622B analog parametric equal-
izer. Therefore, unlike less sophisticated digital equalizers that use the
“bilinear transformation” to generate EQ curves, the shapes of the
8700i’s curves accurately emulate an analog equalizer, even at high fre-
quencies.
Midrange Parametric Equalizer is a parametric equalizer whose boost and cut curves
closely emulate those of an analog parametric equalizer with conventional bell-
shaped curves.
Mid Frequency determines the center frequency of the equalization, in
Hertz. Range is 250-6000 Hz.
Mid Gain determines the amount of peak boost or cut (in dB) over a

10
dB range.
Mid Width determines the bandwidth of the equalization, in octaves. The
Equalizer Controls
Group
Basic / Full
Modify Name
Advanced Name Range
Bass Shelf
BASS FREQ Bass Frequency
80, 85, 90, 95, 100, 105, 110, 115,
120, 125, 130, 135, 140, 145, 150,
160, 170, 180, 190, 200, 210, 220,
230, 240, 250, 270, 290, 310, 330,
350, 380, 410, 440, 470, 500 Hz
BASS GAIN Bass Gain
0 … 12 dB
BASS SLOPE Bass Slope 6,12,18 dB / Oct
Low
LF FREQ Low Frequency 20 ... 500 Hz
LF GAIN Low Gain
–10.0 … +10.0 dB
LF WIDT Low Width 0.8 ... 4 octaves
Mid
MID FREQ Mid Frequency 250 ... 6000 Hz
MID GAIN Mid Gain
–10.0 … +10.0 dB
MID WIDTH Mid Width 0.8 ... 4 octaves
High
HIGH FREQ High Frequency
1.0 … 15.0 kHz
HIGH GAIN High Gain
–10.0 … +10.0 dB
HIGH WIDTH High Width 0.8 ... 4 octaves
Brilliance BRILLNCE Brilliance
0.0 … +6.0 dB
HF Enhancer
HF ENH
High Frequency
Enhancer
0 … 15
Subharmonic
Injection
SUBHARM
Subharmonic In-
jection
Off, −
B
DJ Bass
(5B only)
DJ BASS DJ Bass Boost
Off, 1… +10 dB
Rumble Fil-
ter/30 Hz HPF
30 HZ HPF Off/On
Phase Rotator Phase Rotate Off/On
Phase
Corrector /
Phase Corr Phase Corrector
On…Off
Multipath
Mitigator Phase Corr
Xover Phase Corrector
Crossover
62.5…796 Hz
Table 3-2: Equalization Controls