Meyer Sound Laboratories Inc M3D
™
Line Array
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11
HYBRID LINE ARRAYS
The M3D is a high-powered BroadbandQ™ loudspeaker
system. In order to effectively array, drive, and optimize
a system to produce optimal results, it’s important to
understand how a hybrid line array loudspeaker works.
For high frequencies, the M3D takes advantage of the
control that wave guide horns provide. In the horizontal
pattern of the array, these horns work just as any wave
guide does to produce a consistent beamwidth of
coverage. In the vertical, however, the REM™ is designed
to produce very narrow coverage in order to minimize
destructive interference between adjacent elements and
maximize throw. As more elements are arrayed in a
vertical column, they throw high-frequency energy more
effectively through coupling. The amount of energy can
then be controlled using the relative splay between the
elements.
For the mid-to-low frequencies, it’s important to
understand that even though the M3D’s Broadband Q™
technology will maintain front-to-back attenuation from
580 Hz down to 35 Hz, line arrays must be coupled
together to narrow their vertical polar response and
throw mid and low energy to the far field. The more
elements used, the narrower the vertical beamwidth
becomes. (See Figure 20.)
Adjusting a Line Array’s Coverage
The most effective method for adjusting a hybrid line
array’s vertical coverage is to adjust the mechanical
splay between the elements. (Horizontal coverage for a
single array is constant.) Narrower vertical splay angles
produce a higher-Q vertical beamwidth, while wider
splay lowers the Q. The following is a case example
showing a design where this principle is applied to a
sloped outdoor venue.
Figure 20. Eight versus sixteen M3D line arrays
250 Hz
125 Hz
eight
M3Ds
sixteen
M3Ds
sixteen
M3Ds
eight
M3Ds