Sx
500+
400-Watt Two-Way
Speaker System
• Ring-Mode Decoupling (RMD
TM
)
Technology for increased intelligibility
• Durable structural-foam enclosure with
integral handles and stand mount
• DL15Sx 15-inch woofer and DH2T
compression driver for great sound and
reliable performance
• Asymmetric constant-directivity
75° x 60° high-frequency horn
• Asymmetric horn-loaded woofer section
• 400-watt long-term rms power capacity
• Molded-in attachment points for secure
suspension with optional brackets
• Dual Neutrik Speakon
®
high-current
connectors
• Biampable, passive network with PRO™
circuit for high-frequency driver
protection
Description
The Electro-Voice Sx500+ is a 400-watt,
15-inch two-way, biampable, high-effi-
ciency, constant-directivity speaker system
featuring a vented-horn woofer section.
Through extensive use of computer-aided
design and modeling, Electro-Voice engi-
neers have developed a state-of-the-art pro-
fessional loudspeaker system.
The high-frequency section of the Sx500+
utilizes a molded-in 75° x 60° constant-di-
rectivity horn which is aimed downward by
10°. This unique pattern contributes to high
intelligibility and aims the speaker's output
where it is most useful. Vocals sound natu-
ral yet “cut through” in reverberant, noisy
rooms. In addition, the coverage pattern is
unusually uniform over its range of opera-
tion. The horn’s unique, VariPath
TM
throat
geometry helps direct driver output to the
corners of the room, to points of coverage
not described in the usual specifications of
horizontal and vertical coverage angles, and
to parts of the audience that typically do not
receive the strongest coverage.
One of the many other unique features of the
Sx500+ is the cabinet. Constructed of high-
impact polypropylene structural foam, it pro-
vides a stiff and extremely durable enclosure.
The cabinet includes integral carrying
handles and a stand socket for mounting on
1
3
/
8
-inch stands such as the Electro-Voice
100BK. Rubber feet that are attached to the
bottom of the cabinet and mating sockets that
are molded into the top provide a means of
stacking systems. The shaped plastic cabi-
net, in combination with the uniform, 75° x
60° directivity characteristics, make the
Sx500+ ideal for use alone or in arrays.
The Sx500+’s high-frequency horn is driven
by the DH2T one-inch throat, wide-band-
width, titanium-diaphragm driver. This
driver uses a unique, convex-drive Time
Path
™
phasing plug structure (U.S. Patent
#4,525,604) for smooth and extended high-
frequency performance. The voice coil is
coupled to the diaphragm with EV’s exclu-
sive Resonant Drive™ Technology. This in-
creases and smooths the high-frequency re-
sponse and reduces the amount of internal
equalization required for flat frequency re-
sponse, which extends to 16,000 Hz.
A self-resetting high-frequency protection
circuit, EV’s PRO™ circuit, is included with
the Sx500+ to prevent against accidental
overdrive and improve system reliability. If
the input power to the high-frequency driver
exceeds the nominal rating, the protection
circuit is activated and reduces the power
delivered to the driver by 6 dB. The system
will remain in this mode of operation until
the input power is reduced to a safe level.
The bass section of the Sx500+ is a vented-
horn design using Thiele-Small parameters
for solid performance to 43 Hz. This horn
provides directivity control for the woofer
section and matches the asymmetry of the
high-frequency section. The 381-mm
(15-in.) DL15Sx woofer used is a specially
designed unit featuring an extended-length
voice coil and high-temperature construction
materials. The system combines profes-
sional-quality components, arranged in an
unusually durable Thiele-Small-aligned
vented enclosure. The result is clear and ar-
ticulate, high-quality sound.
Ring-Mode Decoupling (RMD
TM
)
Technology
The Sx500+ controls both acoustical and me-
chanical ring modes to provide dramatically
increased intelligibility, using techniques
learned from the development of the Electro-
Voice X-Array™ concert speakers. There is
much less coloration of the sound from reso-
nating sources, leaving only the intended
sound to be heard by the audience. The most
obvious implementation of RMD™ on the
Sx500+ is the foam attached to the back of
