Behringer DSP8024 User Manual

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ULTRA-CURVE PRO DSP8024
To obtain the best results the following points should be paid close attention to:
Experience has shown that, before beginning to use the equalizer, it is sensible to listen to a variety of music
and speech material with which you are thoroughly familiar, playing these references “straight” through the
system without any corrective EQ. Should any form of distortion, or unwanted effect be noticed, it will most
likely be due to overloading or signal mismatch within the system, which should first be corrected.
The importance of loudspeaker positioning cannot be overemphasized! There is no equalizer available which
can compensate for sound which is “washed out”, imprecise and unclear due to interference from walls or
ceilings. You can achieve drastic improvements in sound quality by careful repositioning of your loudspeakers.
In the case of an active system with two, three or more loudspeakers served by a crossover you must pay particular
attention to travel path time differences and phase coherence between the different components of the system. (The
BEHRINGER SUPER-X PRO CX2310 and CX3400 crossovers, with variable crossover frequency settings, phase
reverse and electronic time path correction give you all the tools required to carry out these corrections.)
Once the above points have been attended to, the ULTRA-CURVE PRO may be put to work. By using the automatic
measurement procedure you will quickly get a usable basic EQ setting. Pay particular attention to the placement of
the reference microphone. It should be placed in the direct radiation path of the loudspeaker system and may not be
interfered with by anything causing a disturbance in the room acoustic. Placement behind curtains, less than three
feet from side or rear walls, or on a balcony is to be avoided, as these positions inevitably exhibit a “colored”, false
acoustic. Background noise should be at least 6 dB (preferably 10 dB) below the nominal working level, otherwise
it will influence the measurement to the extent that it cannot be relied upon to proceed with a workable system
equalization. Disturbances such as mains hum, or narrow band resonances may be effectively eliminated with the
ULTRA-CURVE PRO’s parametric filters. They should be dealt with before proceeding with a measurement.
After the automatic measurement has been completed you have a basic setup, which you should start to finely
adjust manually.
A linear or “flat” frequency response is not always the setting to go for. In the case of a system which will be
used for speech purposes, the priority has to be ease of intelligibility, which requires that the bass response of
the system should fall off. Anything below the fundamental frequency of speech will cause problems.
Very low and high frequencies will usually be amplified (carried over) to a much lesser extent. There is no
sense in driving a loudspeaker cabinet designed only for speech/vocal use hard at frequencies below 50 Hz.
Apart from the increase in power required, this can also result in very expensive loudspeaker repairs.
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Always be aware of and work within the physical limitations of your system.
If time allows make several measurements with the reference microphone in different positions. The next figure
shows some suitable positions for taking measurements.
Fig. 3.2:  Recommended positions for measurements with the reference microphone
3. APPLICATIONS