Behringer FBQ3102, FBQ6200 Application Examples, Master equalizer in sound reinforcement systems

ULTRAGRAPH PRO FBQ1502/ULTRAGRAPH PRO FBQ3102/ULTRAGRAPH PRO FBQ6200

+Try to orient yourself on a frequency whose signal level lies in the 0 dB to -3 dB range in order to avoid overdriving the equipment connected (e.g. power amplifier, crossover).

2.3.3 Subwoofer section

The LED display indicates the signal level present at the SUB OUT connector.

The signal level present at the subwoofer output connector can be adjusted by using the LEVEL control.

To activate the subwoofer output, please depress the SUBWOOFER switch.

In general, the location of a subwoofer is not critical, since the source of deeper freqencies is not easily determined. However, to achieve optimal sound resolution, you should try to position the subwoofer in a central location between the two main speakers. This way, you minimize run-time differences and the sound quality deterioration associated with them.

3. APPLICATION EXAMPLES

The flexible concept of the ULTRAGRAPH PRO models, with the diverse possibilities in sound processing, open up an entire range of application possibilities for you.

Fig. 3.1: The ULTRAGRAPH PRO FBQ6200

as master equalizer

3.1Master equalizer in sound reinforcement systems

This diagram shows a typical set-up with the ULTRAGRAPH PRO models (see fig. 3.1).

To achieve optimal results, you should pay attention to several issues:

Before you start correcting the frequency response of a setup, it is advisable to first let the music and other sound sources run “uncorrected”, as this is something that has proven itself in practice. If distortion occurs, such overdriving is the first issue to be overcome in your setup. Loudspeaker location is also very important. No equalizer in this world can significantly correct the dull sound created through reflexion of wall structures and ceilings. Often, very dramatic improvements can be made by simply placing and aligning speakers correctly.

If you are using an active multi-way system you should take some run-time and phase correction measures before you work with the ULTRAGRAPH PRO (our crossover network SUPER-X PRO CX3400 provides all the necessary tools with its variable split frequencies, phase reverse switches and electronic run-time correction facility). Only after making these preliminary adjustments should you start implementing them on your ULTRAGRAPH PRO.

Disturbing noise (e. g. mains-induced hum) as well as narrow- band resonances should first be tackled by using the ULTRAGRAPH PRO (also see ch. 3.2.1). You should definitely perform all these adjustments before modifying the overall sound.

Now you have a basic setup and now it’s time to start fine- tuning your sound.

Some ground rules:

A linear response curve is not ideal for every application. For example, when dealing with the spoken word, intelligibility is what is most important. Therefore, the transmission curve should drop off in the bass segment of the signal because otherwise only interference is transmitted.

In general, extremely low and high frequencies are transmitted with much lower amplitudes. There is no sense in “forcing” a small full-range speaker to reproduce frequencies below 50 Hz; apart from a need for higher power reserves, speaker damage will be the most likely result.

+Always respect the physical limitations of your system.

After setting up your system as precisely as possible to the desired transmission curve, walk around the venue in order to get an impression of what your signal sounds like in different locations. Do not forget to take regular breaks while you do this, and also try to use various program sources to truly develop a feeling for what your system really sounds like and how the venue carries the sound.

+Setting up your equalizer well takes a lot of time and patience! If you notice that only extreme settings on your equalizer create a usable frequency response, this is probably a good indication that a cardinal mistake may have been committed elsewhere in the P.A. system or room acoustics.

An equalizer is no solution for bad equipment, but it is an extremely useful and effective sound tool for musical fine-tuning. Fine-tuning often leads to amazing improvements in acoustic penetration and in the overall sound quality of your entire setup.

3. APPLICATION EXAMPLES 7