Orban OPTIMOD 6300, Руководство по эксплуатации

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OPERATION ORBAN MODEL 6300
solid, punchy bass from the better consumer receivers and home theater systems
with decent bass response. The 6 dB/octave shelving boost is like a conventional
tone control and creates the most mid-bass boost, yielding a “warmer” sound. Be-
cause it affects the mid-bass frequency range, where the ear is more sensitive than it
is to very low bass, the 6 dB/octave slope can create more apparent bass level at the
cost of bass “punch.”
There are no easy choices here; you must choose the characteristic you want by
identifying your target audience and the receivers they are most likely to be using.
Often, you will not want to use any boost at all for general-purpose sound-for-
picture programming because this can exaggerate rumble and other low frequency
noise. Additionally, large amounts of boost will increase the gain reduction in the
lowest band of the multiband compressor, which may have the effect of reducing
some frequencies below 100 or 200 Hz (depending on the setting of the
B1/B2
X
OVER
control). So be aware the large fixed bass boosts may have a different effect
than you expect because of the way that they interact with the multiband compres-
sor.
On the other hand, stations specializing in pop music programming will usually want
to employ some bass boost to maintain the punch of this programming, particularly
if urban or rap music is a significant part of the music mix.
Low Frequency Parametric Equalizer is a specially designed equalizer whose
boost and cut curves closely emulate those of a classic Orban analog parametric
equalizer with conventional bell-shaped curves (within

0.15 dB worst-case). This
provides warm, smooth, “analog-sounding” equalization.
LF FREQ determines the center frequency of the equalization, in Hertz.
Range is 20-500Hz.
LF GAIN determines the amount of peak boost or cut (in dB) over a

10
dB range.
LF 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, 1.5 octaves is a good starting point. These curves are relatively
broad because they are designed to provide overall tonal coloration, in-
stead of notching out small areas of the spectrum.
The LF parametric can be used in the mid-bass region (100-300Hz) to add “warmth”
and “mellowness” to the sound when boosting. When cutting, it can remove a
“woody” or “boxy” sound.
The equalizer, like the classic Orban analog parametrics such as the 622B, has con-
stant “Q” curves. This means that the cut curves are narrower than the boost curves.
The width (in octaves) is calibrated with reference to 10 dB boost. As you decrease
the amount of EQ gain (or start to cut), the width in octaves will decrease. However,
the “Q” will stay constant.
“Q” is a mathematical parameter that relates to how fast ringing damps out. (Tech-
nically, we are referring to the “Q” of the poles of the equalizer transfer function,
which does not change as you adjust the amount of boost or cut.)