Owner`s manual

PAGE 37 Community Solutions™ Owner’s Manual
13.4 Generic Electronic Control (Non-Community)
It is technically possible to use generic signal processing equipment such as DSP signal processors,
analog EQs, and limiters to set up workable and reasonable operating parameters for the SLS and SBS
loudspeakers. Bear in mind that dynamic equalization, IntelliSense™ protection and certain other
parameters built into Community’s controllers are virtually impossible to mimic using generic devices.
Also Community cannot provide specific advice or details about the proper settings for generic
devices.
13.5 External Equalization
Equalizers are used to increase or decrease the audio level in particular frequency ranges. The
following points about using an equalizer to boost frequencies should be kept in mind. Our hearing is
much more tolerant of dips or holes in the frequency response of an audio system than it is of peaks in
the response. Therefore, reducing a peak is more important than “filling” a hole in the frequency
response. Equalization boosts can easily cause overloads and clipping in the electronic portion of the
signal chain and will reduce gain before feedback when using microphones. The power handling of LF
and HF drivers is the lowest at the extreme low and high frequencies. This is where they are also
producing less output leading to a temptation to apply boosts at that point. Lastly, it does little good
for the performance or the reliability of a loudspeaker to boost any frequencies that are beyond the
specified operating range of the loudspeaker.
For the reasons stated above, it is recommended that only minimal amounts of equalization boost be
used and only for more subtle improvements in the frequency response or to adapt the system to
difficult acoustic environments.
13.6 Acoustic Level Precautions
Various studies have shown that acoustic levels in excess of 100 dB SPL can be damaging to human
hearing. The higher the level above this point the shorter the time the human ear can tolerate it.
Levels near or above 120 dB SPL are physically painful and will, after a very short exposure time
measured in minutes, permanently damage hearing. FIGURE 15 shows the maximum exposure times at
levels from 90 to 115 dBA SPL from two different authorities. Although they differ at lower levels, at
110 dBA they (and others) agree that the maximum acceptable exposure time is only a few minutes.
FIGURE 14: Effects of Amplifier Clipping