Placement; Room Acoustics - Mackie Thump 12A Owner's Manual

Placement

Thump loudspeakers are designed to sit on the floor
or stage as the main PA or as monitors. They may also be
pole-mounted via the built-in socket on the bottom of
the cabinet. Be sure the pole is capable of supporting
the weight of the loudspeaker. The SPM200 is a great
option when using a subwoofer.
WARNING: These Thump loudspeakers do
not have rigging points and are not suitable
for rigging. NEVER attempt to suspend
a Thump loudspeaker by its handles.
Check to make sure that the support surface
(e.g. floor, etc.) has the necessary mechanical
characteristics to support the weight of the
loudspeaker(s).
When pole-mounting loudspeakers, be sure that they
are stabilized and secured from falling over or being
accidentally pushed over. Failure to follow these
precautions may result in damage to the equipment,
personal injury, or death.
As with any powered components, protect them from
moisture. Avoid installing the loudspeaker in places
exposed to harsh weather conditions. If you are setting
them up outdoors, make sure they are under cover if
you expect rain.
Thump loudspeakers are NOT designed to array
horizontally. If you feel you must put two speakers
side-by-side, you should have a good understanding
of the relationship between the splay angle (the angle
between the facing sides of the cabinets) and frequency
cancellation effects between cabinets.
When two cabinets are positioned side-by-side
such that the rear-angled faces of the enclosures
are parallel, the splay angle will be 90º. This matches
the 90˚ horizontal coverage pattern of each individual
loudspeaker; the interference between the two cabinets
will be minimized, but the total coverage of 180˚ may
be too wide for some applications. The mid and high
frequencies may also be reduced for those in the center
who are too close to the loudspeakers.
Reducing the splay angle will reduce the total
horizontal coverage, but it also creates an area both
speakers are covering. Instead of a nearfield hole,
this will cause comb-filtering effects in the frequency
response in the overlapping area. The smaller the splay
angle, the more energy will be delivered on-axis, but the
comb-filtering effects will get worse at the same time.
To reiterate, though, we strongly suggest
NOT arraying these loudspeakers horizontally.
Experimentation and experience will help you find
the right balance for your application.

Room Acoustics

Thump 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 Thump loudspeakers
helps to minimize the problems that typically arise.
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up to 23 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.
• 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.
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