SB-1
Why did Meyer create the SB-1?
The SB-1 is intended to solve one of the most common problems in
large-scale reinforcement: assuring effective high-frequency reproduction
at great distances from the main PA.
Traditional solutions for long-range high-frequency projection have
employed narrow-coverage horns (also called “long throw” horns). But
the sound pressure produced from a horn decreases by 6 dB with each
doubling of distance from the source, and this substantially limits its
useful range. Certain methods for stacking or arraying horns can
increase the system’s throw by effectively moving the acoustical source
farther behind the array, but these techniques break down at
propagation distances greater than about 100 feet.
The SB-1 Sound Beam is the first practical alternative to horns for
large-scale long-throw applications. It produces sound waves whose SPL
decreases by as little as 3 dB per doubling of distance, with flat
response and consistent bandwidth over five octaves — and its pattern
remains consistent for distances up to 500 feet.
What Meyer systems is it designed to work with?
The SB-1 can be used to supplement any large-scale long-throw main PA
system, including those comprised of MSL-3s, MSL-4s, MSL-5s, MSL-6s,
or MSL-10s in any combination.
Meyer
Sound
Q&A
The Meyer Sound SB-1
Parabolic Sound Beam is
a powerful, long-throw
device for projecting
mid- and high-frequency
energy over distances
from 100 to 500 feet.
By producing an
extremely narrow, tightly
controlled beam of sound
energy, the SB-1 enables
very effective long-range
“fill” coverage in largescale sound reinforcement
applications.
The SB-1 comprises an
optimized aspherical
waveguide with 2-inch
throat (4-inch
diaphragm diameter)
compression driver
feeding a large parabolic
reflector, and a 12-inch
cone driver mounted at
the center of the reflector.
Built-in electronics
include dual
complementary
MOSFET class AB/H
amplifiers with 1240
watts total power output,
TruePower™ Limiting
driver protection, and
frequency and phase
response alignment
circuitry. This powerful
combination of
components provides flat
response from 500 Hz to
15 kHz and 110 dB
peak SPL output at
100 meters.
PATENT PENDING
Why use the SB-1 rather than delayed loudspeaker arrays?
Delayed loudspeakers are a common and effective alternative to longthrow horns, but there are some constraints in their application.
As shown in Figure 1a, because the fill speakers are physically separated
from the main array(s), they can only be aligned for seats that lie
directly on their primary axis. For all other seats in their coverage area,
varying differences in path length from the main PA can cause
cancellations that degrade the frequency response. In small-to-moderate
sized installations, the path length differences are generally small
enough that cancellations occur only at very high frequencies. But in
large-scale applications requiring very long throws, cancellations can
develop in the upper midrange, where they can be much more
destructive of fidelity.
By contrast, because of its ability to project over very long distances,
the SB-1 can be placed with the main PA array. When the fill coverage
emanates from the same physical location as the main system, pathlength differences are eliminated, and flat response can be achieved
with far fewer system adjustments.
In enclosed performance arenas, delay speakers also excite the
boundaries of the space from multiple locations, producing uncorrelated
reflections that compromise intelligibility. This problem can be minimized
by carefully controlling the speakers’ coverage patterns and bandlimiting their response, but only at the expense of complicating the
system design and its setup/alignment.
Because the SB-1 maintains consistent 10-degree coverage across its
full range of operation, it can be arrayed and aimed so that virtually all
of its energy falls on — and is substantially absorbed by — the
audience. Destructive reverberation is greatly reduced, the “critical
distance” substantially increases, and clarity is enhanced. Indeed,
listeners have commented that the SB-1 makes a large sound system
seem much closer to them, as though they were listening to studio
monitors in the near field!
How does the SB-1 work?
The SB-1 achieves a very narrow coverage angle and plane-wave
propagation by taking advantage of a large paraboloid reflecting surface.
A parabola is a simple, mathematically-described curve (Figure 2a) that
possesses a unique focal point. A paraboloid surface is formed by
sweeping a parabola around the primary axis that extends through
center of the curve and its focus, so as to describe a three-dimensional
dish. If sound energy radiates from a source at the focus and is directed
onto the paraboloid surface, it is reflected outward in a path parallel to
the curve’s primary axis (Figure 2b). The paraboloid thereby becomes a
highly directional emitter of plane (flat) wavefronts which are capable of
propagating over long distances with minimal loss — much like an
acoustic spotlight.
Despite the efficiency of parabolic reflectors, they have not been used
in sound reinforcement until now because conventional designs are
hampered by a limited frequency range (with substantial lobing in the
lower frequencies) and inconsistent beamwidth (varying with frequency).
The SB-1 addresses and overcomes both of these shortcomings.
Low-frequency lobing is controlled in the SB-1 by a 12-inch cone driver
SB-1
Q&A continued
Meyer
Sound
A
B
x
y
focus
Figure 1A
Figure 2A
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