Room Acoustics - Mackie SRM450v3 Owner's Manual

Room Acoustics

SRMv3 loudspeakers are designed to sound fantastic
in nearly every application.
But, room acoustics play a crucial role in the overall
performance of a sound system. However, the wide
high-frequency dispersion of the SRMv3 loudspeakers
helps to minimize the problems that typically arise.
Top
90 Dispersion
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up to 20 kHz
Here are some additional placement tips to help
overcome some typical room problems that might arise:
• Placing loudspeakers in the corners of a room
increases the low frequency output and can
cause the sound to be muddy and indistinct.
• Placing loudspeakers against a wall increases
the low frequency output, though not as much
as corner placement. However, this is a good
way to reinforce the low frequencies, if so
desired.
• Avoid placing the speakers directly on a
hollow stage floor. A hollow stage can resonate
at certain frequencies, causing peaks and dips
in the frequency response of the room. It is
better to place them on a sturdy stand designed
to handle the weight of the loudspeaker.
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SRM350v3 and SRM450v3 Powered Loudspeakers
90
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• Position the loudspeakers so the high-
frequency drivers are two to four feet above
ear level for the audience (making allowances
for an audience that may be standing/dancing
in the aisles). High frequencies are highly
directional and tend to be absorbed much
easier than lower frequencies. By providing
direct line-of-sight from the loudspeakers
to the audience, you increase the overall
brightness and intelligibility of the sound
system.
• Highly reverberant rooms, like many
gymnasiums and auditoriums, are a
nightmare for sound system intelligibility.
Multiple reflections off the hard walls, ceiling,
and floor play havoc with the sound. Depending
on the situation, you may be able to take some
steps to minimize the reflections, such as
putting carpeting on the floors, closing
draperies to cover large glass windows, or
hanging tapestries or other materials on the
walls to absorb some of the sound.
However, in most cases, these remedies are not
possible or practical. So what do you do?
Making the sound system louder generally
doesn't work because the reflections become
louder, too. The best approach is to provide as
much direct sound coverage to the audience
as possible. The farther away you are from
the speaker, the more prominent will be the
reflected sound.
Use more speakers strategically placed so they
are closer to the back of the audience. If the
distance between the front and back speakers
is more than about 100 feet, you should use a
delay processor to time-align the sound. (Since
sound travels about 1 foot per millisecond, it
takes about 1/10 of a second to travel 100 feet.)
Keep in mind that the speaker mode and feedback
destroyer are two great ways to compensate for some of
these issues. See page 11 for more information [8, 9].