Meyer Sound UPA-1P - Manual (Page 3)

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Introduction
The Integrated Design
The Meyer UPA-P Series (UPA-1P, UPA-2P) self-pow-
ered loudspeakers are comprised of:
• one 12-inch cone driver and one 3-inch diaphragm
compression driver;
• phase-corrected, optimized control electronics;
• a two-channel amplifier (350 W rms /ch).
The drivers, control electronics, and amplifier are inte-
grated into a compact, trapezoidal enclosure. The UPA-P
Series is ideally suited for compact, high-powered PA appli-
cations, such as main PA, churches, surround systems,
and theatres. In addition the UPA-P is an excellent solu-
tion for use under-balcony, ordown-fill, or front fill and
even as a musical instrument speaker.
The UPA-P Series, more than a powered version of the
Meyer UPA-C Series (UPA-1C, UPA-2C), implements these
significant design improvements:
• The gain structure between the control electronics
and amplifier is perfectly matched.
• The amplifier is optimized for the system, providing
substantial power without endangering the drivers.
• The integrated design simplifies setup and instal-
lation, eliminates amp racks, and extends the dura-
bility and reliability of the loudspeaker.
The UPA-P produces flat acoustical phase and amplitude
response, full-range bandwidth, precise imaging, and
exceptional system impulse response. The UPA-P sup-
plies a maximum SPL of 132.5 dB at 1 m with excellent
intelligibility, without the distortion or coloration commonly
exhibited by small PA speakers.
The UPA-P Horns: Constant-Q
As a part of its research and development efforts, Meyer
Sound has solved the most difficult problems associated
with horn design. In order to appreciate the significance
of this work, it is necessary to define an often misunder-
stood term: the beamwidth of a horn is the angle at
which the sound pressure at a given frequency decreases
to half (–6 dB) its on-axis amplitude. Specifying beam-
width using the –6 dB points has been proposed as the
audio industry standard and Meyer Sound adheres to
this definition.
NOTE: In the past, beamwidth was often used to describe
the angle at which the sound pressure decreased 10 dB
from its on-axis amplitude because many listeners per-
ceive -10 dB as a halving in pressure. Meyer Sound
defines beamwidth as the angle at which sound pressure
decreases 6 dB. -6 dB represents the actual halving of
sound pressure. When reading a beamwidth specifica-
tion, it is essential to determine whether it refers to the –6
or –10 dB points. As the two standards produce very
different results: the –10 dB points yield a wider angle.
Previous technologies produced horns whose beamwidth
varied over the operating frequency range. These horns
also displayed nonuniform frequency response within,
and significant side lobe energy outside their beamwidth.
Both undesirable characteristics, particularly prevalent
for horns with a wide beamwidth, make array design
extremely problematic.
The UPA-P was developed in Meyer Sound’s anechoic chamber
by measuring coverage patterns using angular and fre-
quency resolutions of 1° and 1/36 octave, respectively.
The UPA-P horns exhibit constant-Q: the beamwidth re-
mains consistent across the horn’s operating frequency
range in both the vertical and horizontal planes. The
UPA-2P horn’s narrow beamwidth (45°H x 45°V) per-
mits precise coverage with minimal interaction between
neighboring array elements. The UPA-1P horn’s wide
horizontal beamwidth (100°H x 40°V) addresses a larger
coverage area with fewer speakers.
Both speakers share the following remarkable attributes:
• uniform frequency response within the beamwidth
• rapid and uniform amplitude attenuation for all
frequencies outside the beam width
• minimal side lobes