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EUROLIVE B212/B215
3.4 Loudspeaker protection
by using a low-cut filter
Try to prevent damage to your speakers caused by extreme
oscillation of the bass membrane due to subsonic noise and
extremely deep frequencies. Use an equalizer to cut off those
frequencies that fall below your speakers’ frequency range, or
use a low-cut/high-pass filter. Most equalizers and sound-
improvement systems offer a low-cut function, like the
BEHRINGER ULTRAGRAPH DIGITAL DEQ1024, for example.
Using a low-cut filter in your signal path is particularly recommended
if you use record players or CD players as your signal source. CD
players often produce extremely deep frequencies, which can
lead to extreme excursions of the bass membrane.
4. ADDITIONAL CONSIDERATIONS
4.1 Length and diameter of loudspeaker cables
Loudspeaker cables whose diameter is too small can
considerably limit the power amp performance. The longer the
cable, the more pronounced the problem. As a result, musicians
often simply “turn up” the amp, which can lead to loudspeaker
damage. Therefore, don’t use cables longer than 15 m (45 ft.).
For most applications, this will not be necessary. Cable diameter
should be at least 2.5 - 4.0 mm
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4.2 Power amp rating
Selecting the right amp can turn out to be rather difficult.
Therefore, stick to the following rule of thumb: the power rating
of your amp should be roughly twice the speaker load capacity.
A speaker rated at 200 Watts continuous performance can easily
be powered by an amp rated at 400 Watts output power. An
optimal addition to your speaker system would be the BEHRINGER
EUROPOWER EP1500 power amp, for example.
4.3 Fuses
We do not recommend the use of fuses with audio applications.
Damage to loudspeakers can be the result of high peak signals
and high output power. However, fuses can only offer protection
from one of these two factors, and never from both. Additionally,
fuse resistors are sometimes nonlinear, leading to distortion and
unpredictable overdriving.
4.3.1 Protecting your equipment
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Always try to find the optimal signal level. Try to avoid
overdriving your amp.
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Keep in mind the physical limitations of your PA system.
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Use a limiter to restrict the output signal level. Place the
limiter between the mixing console and the power amp. For
this purpose, our proven AUTOCOM PRO-XL MDX1600,
COMPOSER PRO-XL MDX2600 and MULTICOM PRO-XL
MDX4600 compressors offer an outstanding solution. All
models can be used as a limiter: the audio signal doesn’t
overdrive any more, and unpleasant “peaks” are effectively
avoided.
Our ULTRADRIVE PRO DCX2496 and SUPER-X CX3400/
CX2310 crossovers are particularly well-suited for
protecting your equipment: for each output, they
have independent limiters.
5. APPLICATION EXAMPLES
5.1 Full-range stereo operation
In the following example, the main output signal of a mixing
console is connected to a power amplifier. Both the outputs and
inputs are stereo. A B212/B215 is connected to each of the amp
outputs, and these speakers reproduce the entire frequency
range (a full range).
Fig. 5.1: Full-range stereo operation
5.2 Using several B212/B215 loudspeakers
For larger rooms, you can connect several B212/B215 speakers.
Fig. 5.2: Wiring several B212/B215 loudspeakers
5. APPLICATION EXAMPLES
