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mounted at the center of the dish. The cone is driven by special band-
limiting and phase manipulating circuitry that uses phase cancellation to
suppress side lobes in the range of 500 Hz to 1 kHz. This sophisticated
scheme reduces the amplitude of the side lobes by over 50 dB,
substantially extending the usable mid-frequency response.
Constant beamwidth with frequency is achieved by feeding the SB-1
reflector from an optimized aspherical horn that is placed at the focal
point of the dish. Developed using high-resolution measurement in an
anechoic environment, this horn enables the SB-1 to achieve a uniform
10-degree beamwidth at frequencies up to 15 kHz.
Is the SB-1 made for permanent installations only, or is it portable?
The SB-1 physical packaging has been designed to satisfy both fixed and
portable applications. For shipping, the high-frequency pod and its
mounting arms are disassembled and packed in a stowage space that is
accessed through a hatch on the top of the dish. A removable front
cover protects the dish surface and 12-inch cone from damage, and the
enclosure is fitted with handles so that it can be easily maneuvered.
How is it mounted/rigged?
Meyer Sound offers a mounting yoke. Fabricated of heavy-gauge steel
tubing, this rugged rigging fixture suspends the SB-1 dish from one point
on each side, allowing it to be swung through more than 300 degrees
for maximum freedom of vertical aiming. Two hanging points (one on
either side) are provided so that the assembly can be flown.
Alternatively, the yoke allows placing the SB-1 free-standing on a
scaffold or catwalk above the main system.
How is the SB-1 arrayed and aimed?
The SB-1 provides a consistent 10 degrees of coverage over a range of
100 to 500 feet and projects a circular coverage pattern. Best
performance is attained when multiple units are placed with the main PA
array and splayed in an arc at 8 degree angles. This provides a slight
overlap between the patterns of adjacent units for more even coverage.
A surveyor's transit, placed atop the cabinet for sighting, is handy for
fine adjustments in aiming.
How can I predict coverage from the SB-1 when planning a system
installation?
The SB-1 projects a circular pattern with a consistent 10-degree coverage
angle. As a rule of thumb, the diameter of the projected circle can be
estimated by multiplying the distance from the SB-1 by .175 — so, at
300 feet, for example, the maximum coverage diameter is about 53 feet.
Alternatively, if you are working from a plan view of the venue, you can
use a protractor to lay out 10-degree coverage wedges (remember to
overlap them eight degrees center-to-center for smoother coverage).
What is the maximum distance at which the SB-1 will project over
100 dB SPL?
Figure 2B
Under ideal conditions, the SB-1 can deliver over 100 dB SPL at its full
design throw of 500 feet. In practice, however, the SPL at long distances
can be affected by atmospheric conditions — especially at the highest
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