Orban Optimod-PC 1101, Operating Manual

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OPERATION ORBAN MODEL 1101
Bass Shelf Controls , the Five-Band structure’s low bass equalization controls, are
designed to add punch and slam to rock and urban music. They provide a parametric
shelving equalizer with control over gain, hinge frequency, and slope (in dB/octave).
Bass Shelf Hinge Frequency sets the frequency where shelving starts to
take effect.
Bass Gain sets the amount of bass
boost (dB) at the top of the shelf.
Bass Slope sets the slope (dB/octave)
of the transition between the top
and bottom of the shelf.
Because the Five-Band structure often
increases the brightness of program
material, some bass boost is usually
desirable to keep the sound spectrally
well balanced. Adjustment of bass
equalization must be determined by individual taste and by the require-
ments of your format. Be sure to listen on a wide variety of consumer sys-
tems—it is possible to create severe distortion on poor quality speakers
by over-equalizing the bass. Be careful!
The moderate-slope (12 dB/octave) shelving boost achieves a bass boost
that is more audible on smaller radios, but which can sound boomier on
high-quality systems. The steep-slope (18 dB/octave) shelving boost cre-
ates a solid, punchy bass from the better consumer 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.
Because 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. Regardless of which curve you use, we recommend a
+2 to +5 dB boost for most formats. Larger amounts of boost will in-
crease the gain reduction in the lowest band of the multiband compres-
sor, which may have the effect of reducing some frequencies. 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 com-
pressor. (The G
REGG
presets use this effect purposely to create a dynamic
cut in the mid-bass.)
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.
Hz
55 110 220 440
0 dB
+3 dB
+6 dB
Bass Gain
Bass Shelf Hinge Frequency
6dB/oct
12dB/oct
18dB/oct
Bass
Slope