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ULTRA-Q PRO PEQ2200
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We would like to draw your attention to our ULTRA-CURVE, a device which combines a digital
31-band graphic equalizer with an on-board analyzer. Please ask your retailer for further
information or contact BEHRINGER directly.
Still, you can achieve satisfying results even without a frequency analyzer. In most cases, the sound image
can be fine-tuned by earwith a little bit of patience.
In general, feedback frequencies are narrow-band in their character. It is this fact that makes the ULTRA-Q
PRO with its narrow-band filters the ideal audio tool. However, it should be noted that in most cases it is not
necessary to cut the resonance frequency completely when feedback occurs. More importantly, it should be
identified as precisely as possible.
The theoretical basics of feedback resonances are quite complex. Of particular importance are the bandwidth
of the resonance frequencies, their phase characteristics and of course the room acoustics.
As already mentioned, any form of boost/cut of narrow frequency bands causes phase shift in the audio path.
The feedback susceptibility depends both on the amplitude and on the phase characteristics of the feedback
loop, a change in amplitude or in phase reduces the risk of feedback. So, if you use a narrow-band equalizer,
the desired change in feedback behavior can be achieved not only by lowering the amplitude but also by
modifying the phase position.
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We would like to draw your attention to our FEEDBACK DESTROYER, a device that identifies
and eliminates up to 24 frequencies automatically. Please ask your retailer for further
information or contact BEHRINGER directly.
In addition to narrow-band notching applications, the BEHRINGER ULTRA-Q PRO can also be used for
broad-band corrections of the frequency response, for example, to simulate a simple tone control circuit, a
frequency crossover network for speaker systems, the sound of specific speaker systems, or simply to modify
sounds dramatically (telephone voice). All of these applications have been quite difficult to realize up to now.
In practice, broad-band frequency correction is the most common application in the field of sound reinforce-
ment systems, for example, to enhance the low-range response and/or to make up for high-frequency loss
caused by room acoustics. Simply use two or three broad-band parametric filters in combination with the two
low and high-cut filters to achieve the desired frequency correction. Another two or three bands could then be
used to minimize feedback or make up for room resonances.
Apart from solving problems of room acoustics, the ULTRA-Q PRO also helps you cope with the problems of
microphone positioning and direction, or improve intelligibility by tweaking the response curve.
Since speaker systems usually have no flat response curve and need to be positioned in accordance with
optical rather than acoustical criteria, the resulting additional problems of room acoustics make the equalizer
an indispensable tool.
6.4 Identifying problems by ear
Maybe you think that frequencies causing problems can best be identified by tuning a narrow-band filter over a
specific frequency range. However, practice has shown that it is easier to identify them by making them heard,
rather than find out which frequencies are lacking. It is therefore useful not to lower the amplitude of the narrow-
band filter, but to raise it first in order to identify the frequency that causes the trouble. Once this frequency has
been identified, you simply reduce the filter in level.
7. EQUALIZERS AS CREATIVE AUDIO TOOLS
The ULTRA-Q PRO is an indispensable audio tool for application in recording studios, stage plays or radio
dramas. You can use it to distort voices, create telephone sounds and filter instruments to make them fit into
the mix-down.
The tables printed below give you some clues as to the acoustic significance of specific frequencies. Please
use them as suggestions for your own experiments with the ULTRA-Q PRO.
7. EQUALIZERS AS CREATIVE AUDIO TOOLS
