The SA1521 is an active 2-way sound reinforcement
speaker system designed for extreme accuracy, high out-
put, and smooth dispersion across the entire audio fre-
quency range. It integrates 500 watts of amplifier power,
active control electronics, and precision components into a
speaker system with 100 dB sensitivity (1 watt @ 1 meter).
The resulting high resolution and clarity in the critical low-
mid and mid-range frequencies are unparalleled for a 15"
loaded, 2-way speaker system.
Several state of the art advancements in transducer
technology have been incorporated in the design of the
SA1521. The compression driver uses a new 1.75-inch
titanium diaphragm featuring a 3-slot, optimized geom-
etry phase plug. When coupled to the low-distortion, high-
output horn, the SA1521 provides uniform power response
and correct phase alignment characteristics at the cross-
over frequency. With the resulting 75° x 65° dispersion
pattern, the SA1521 provides very open, natural sound
reproduction at extreme output levels.
A 15-inch high-efficiency woofer produces tight, punchy
bass. The woofer's magnetic structure delivers an excep-
tional amount of magnetic force and is responsible for the
system's high sensitivity and high efficiency by providing
tight control over the cone's movement. This tight control
over the woofer's moving mass results in unusually smooth
low-frequency response from 50Hz up to the mid-frequency
crossover point at 1300Hz.
The amplifier for the compression driver incorporates a
Class AB topology, renowned for its clarity, warmth, and
high-voltage output to generate extreme SPL levels. A
Class G design is used for the low-frequency amplifier,
which features two power supplies for improved efficiency
and more output power per pound.
A signal panel and a power panel are located on the
amplifier assembly at the back of the cabinet, separated
by a large aluminum heatsink. The signal input panel con-
tains XLR connectors for line-level input and loop-through
connections, a level control, and four status LEDs for
Power ON, Signal Present, Limit, and Thermal functions.
The power switch and IEC AC connector are located on the
The internal processor provides complete system man-
agement of all electronic and acoustic functions. These
include an electronic active crossover, electronic phase
alignment, electronic time correction, electronic equalization,
and complete amplifier and component protection.
To ensure long-term reliability, the amplifiers are
mounted on a massive extruded heatsink, which is convec-
tion cooled and dramatically extends the life expectancy of
the heat-producing components.
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Active 2-Way Sound
Reinforcement Speaker System
Active, High Output/Wide Dispersion
133 dB Peak SPL
Bi-amplification with 400 watts rms low-frequency
and 100 watts rms high-frequency power
Wide dispersion, ultra-low distortion high-
Complete electronic and component protection
15-inch high efficiency, light mass woofer
State-of-the-art precision 1.75-inch titanium
compression driver with 3-slot, low distortion,
optimized geometry phase plug
Electronic equalization, time correction and
Low Frequency Dynamic Bass Protection, RMS
Limiting, Power Supply and Amplifier Thermal
Professional trapezoidal enclosure design
Correctly weight-balanced with two comfort-
able side handles for easy carrying and set up
One top and one bottom handle for easy reposi-
tioning of speaker and built-in pole mount cup
Portable PA Systems
O F 6 P A G E S
o F 6 PAG E S