Orban OPTIMOD 6300, Руководство по эксплуатации

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OPTIMOD 6300 DIGITAL OPERATION
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The curves in the 6300’s equalizer were created by a so-called “minimax” (“minimize
the maximum error” or “equal-ripple”) IIR digital approximation to the curves pro-
vided by the Orban 622B analog parametric equalizer. Therefore, unlike less sophis-
ticated digital equalizers that use the “bilinear transformation” to generate EQ
curves, the shapes of the 6300’s curves are not distorted at high frequencies.
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 FREQ determines the center frequency of the equalization, in Hertz.
Range is 250-6000Hz.
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 range is 0.8-4.0 octaves. If you are unfamiliar with using a parametric
equalizer, 1 octave is a good starting point.
With 5-band presets, the audible effect of the midrange equalizer is closely associ-
ated with the amount of gain reduction in the midrange bands. With small amounts
of gain reduction, it boosts power in the presence region. This can increase the
loudness of such material substantially. As you increase the gain reduction in the
midrange bands (by turning the
M
ULTIBAND
D
RIVE
(Multiband Drive) control up), the
M
ID
G
AIN
control will have progressively less audible effect. The compressor for the
midrange bands will tend to reduce the effect of the
M
ID
frequency boost (in an at-
tempt to keep the gain constant) to prevent excessive stridency in program material
that already has a great deal of presence power. Therefore, with large amounts of
gain reduction, the density of presence region energy will be increased more than
will the level of energy in that region. Because the 3.7 kHz band compressor is par-
tially coupled to the gain reduction in the 6.2 kHz band in most presets, tuning
M
ID
F
REQ
to 2-4 kHz and turning up the M
ID
G
AIN
control will decrease energy in the 6.2
kHz band—you will be increasing the gain reduction in both the 3.7 kHz and 6.2 kHz
bands. You may wish to compensate for this effect by turning up the
B
RILLIANCE
con-
trol.
With 2-band presets, the midrange equalizer will behave much more as you might
expect because the 2-band structure cannot automatically re-equalize midrange en-
ergy. Instead, increasing midrange energy will moderately increase the Master
band’s gain reduction.
Use the mid frequency equalizer with caution. Excessive presence boost tends to be
audibly strident and fatiguing. Moreover, the sound quality, although loud, can be
very irritating. We suggest a maximum of 3 dB boost, although 10 dB is achievable.
In some of our factory music presets, we use a 3 dB boost at 2.6 kHz to bring vocals
more up-front.
High Frequency Parametric Equalizer is an equalizer whose boost and cut curves
closely emulate those of an analog parametric equalizer with conventional bell-
shaped curves.