10
(3) | (4) | (8) |
Fig. 2.10: Active control elements on the rear panel of the
(3)HIGH OUTPUT connector. Output for the High band signal.
(4)
(8)MODE button. In mono
◊Always switch off the entire system before you press this button, as it produces heavy interference noise that could damage your speakers and/or other equipment.
(11)
(12)LOW OUTPUT connector. Output for the Low band signal.
(13)XOVER FREQ. button. This button serves to switch over the control range of the
◊Always switch off the entire system before you press this button, as it produces heavy interference noise that could damage your speakers and/or other equipment.
(14)INPUT connector. Input signal connector.
3. Application
3.1 Tools
The following tools are indispensable for a perfect system alignment. You should by all means try to obtain the speaker specifications from the manufacturer, in order to operate the systems in their proper frequency and level ranges. Use the manufacturer’s documentation to adjust the operating mode and crossover frequencies.
◊BEHRINGER does not assume any responsibility for speaker damage caused by improper handling of the
For making measurements you need a
90 Hz and 15 kHz. Place the microphone about 5 m in front of the speaker system to be measured, in a height where it is on axis with the drivers of the two frequency bands you wish to measure. When setting the levels for the individual frequency bands, delay times and crossover frequencies by means of
a measuring microphone, you should operate only one speaker stack each. Usually, the measuring microphone needs to be repositioned between two specific measurements.
(11)(12) (13) (14)
3.1.2Generator/AnalyzerIn combination with a measuring microphone and a generator producing pink noise that is fed into a channel of your P.A. console, an analyzer gives you a graph that shows how the acoustic energy is distributed among the various frequency bands (usually 1/3 of an octave). The equalizer/analyzer BEHRINGER
When you listen to the overall sound of your system, you should walk around in the audience area and try to detect resonance frequencies or cancellations. The sound should be optimized for the position where most of the audience will be gathered, however, without neglecting other areas. This often means that the system must be operated in mono. Whenever you use technical aids such as analyzers, measuring microphones, etc., you should check the results with your ears.
3.2 Setting the input levels
Both inputs provide a gain boost/cut of up to 12 dB. Normally, the output level of the mixing console and the input sensitivity of the power amp are the same, i.e. 0 dB in the console correspond to 0 dB in the amplifier. In this case, the power amp is fully driven and the
3.3 Setting the output levels
The output levels of the single bands can be raised/lowered by as much as 6 dB. To achieve a linear frequency response in the system, all output levels should be adjusted with the help of an analyzer. Then, mute all outputs except for one to check the crossover frequencies and levels, play back pink noise over the system at an appropriate volume level. Now, when you switch on the adjacent band, the level measured around the crossover frequency should go up by 3 dB. Repeat this process for all crossover frequencies.
3.3.1 FindingCheck the entire frequency response of the system. Rooms have quite an impact on the frequency response of speaker systems, due to resonance and various reflections. So, you cannot expect to achieve a linear frequency response right from the start. Use an equalizer such as our
However, if the frequency response shows some irregularities, it can prove useful to correct it by means of the crossover network, before using an equalizer (EQ). Subsequently, the crossover frequencies must be corrected with an EQ as far as this is possible.