Behringer ULTRA-CURVE PRO DSP8024, Руководство пользователя

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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.
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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
Positions 1 and 2 are about three feet directly in front of the loudspeaker system, positioned halfway between
the middle and high frequency components. These measurements can be used as a control of the basic
system functions.
Position 3 is about seven feet in front of the stage centre. Measurements taken here should show an identical
response above 250 Hz as obtained from positions 1 and 2. Due to the summing of both loudspeaker systems,
the level below 250 Hz should be 3 dB higher.
Position 4 is some way back from position 3, directly in front of the FOH mixing position. (FOH means front of
house). The measurements here should be the same as at position 3, with a lower level.
Positions 5 and 6 are on the axes of the two loudspeaker systems, three feet away from the rear wall. These
measurements are used to detect any problems caused by standing waves or reflections.
Make sure to save the resulting frequency response curves for comparison purposes. Any major differences
between the various measurements should be interpreted as warnings of phase problems within the system or
acoustical problems in the room. If you are not able to deal with the source of these problems (by moving
speakers, or changing the venue), then you can only attempt to find a workable compromise with the equalizer.
For this purpose, the various stored measurements will be of great assistance.
3. APPLICATIONS
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