Barney is on tour, sporting a
high-performance PA featuring a MacPherson Monolith speaker system. The
entire PA fits on the dance floor of a semi trailer, while covering
audiences of up to 8,000.
A little more than half the
arena was set up for the show, with seats sold all the way out to about
120 degrees. The PA hang consisted of two line arrays of Monoliths, one
wide by six deep, at a trim height of about 25 feet (7.6m) for the
bottom speaker. The Monolith is a panel speaker measuring 43-inches
(109cm) high x 22.5-inches (56 cm) wide x 8.5-inches (22cm) deep. Single
Monoliths weigh 128 pounds (58kg). When used to construct line arrays,
the speaker is rotated 90 degrees to the horizontal position and hung
via supplied rigging straps to other Monoliths. Line array technology
uses multiple speakers whose drivers are so placed that the physical
distance between them causes controlled summing of the wavefront in the
horizontal plane. The result is controlled phase cancellation in the
vertical plane, and increased directivity (varying with frequency).
Monolith drivers are mounted in the same plane within the speaker. As
such they are nominally phase-correct and do not require electronic
phase manipulation.
Roll in a road case
containing two Monoliths, remove the lid, attach a speaker to the bumper
bar, raise it a couple of feet, then attach the next speaker. Add
speaker cable as necessary. Repeat this process until finished. Not only
does it go up in a hurry, if the rig points aren’t correct then the
time it takes to lower the array, reset the points, and re-hang are
greatly reduced. And since the array simply hangs there it is not
necessary to aim speakers within the array, further reducing setup time.
Even though the arrays weighed only 768 pounds (349kg) excluding
cabling, two rig points were required to stabilize the array in the
horizontal plane. MacPherson supplies a bumper bar and rigging straps
that fit in the Monolith road case, along with two speakers. In addition
to the rig points on each side of the enclosure, there are also a number
of 3/8-inch (1cm) threaded holes at various points around the speaker
for using pull straps, etc. The holes are filled with flat-head recessed
machine bolts, which can be removed to insert an eyebolt.
It must be mentioned that the
prerecorded source material for the show, including the voices of all
dinosaurs and accompaniment music, was of outstanding fidelity.
Orlando-based Sound Deluxe supplied source material, which was
reference-mixed on Monoliths. Vocal intelligibility was extraordinary—every
word could be understood. The system sounded smooth and neutral. The
Monolith line arrays provided even coverage to the edge of the sold
seats.
