Electro-Voice Sx500+ User Manual

Sx500+

400-Watt Two-Way
Speaker System

• Ring-Mode Decoupling (RMDTM)

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

connectors

• Biampable, passive network with PRO™

circuit for high-frequency driver
protection

®

high-current

Description

The Electro-Voice Sx500+ is a 400-watt,
15-inch two-way, biampable, high-effi­ciency, constant-directivity speaker system
featuring a vented-horn woofer section.
Through extensive use of computer-aided
design and modeling, Electro-Voice engi­neers have developed a state-of-the-art pro­fessional loudspeaker system.

The high-frequency section of the Sx500+
utilizes a molded-in 75° x 60° constant-di­rectivity 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 natu­ral yet “cut through” in reverberant, noisy
rooms. In addition, the coverage pattern is
unusually uniform over its range of opera­tion. The horn’s unique, VariPath
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 high­impact polypropylene structural foam, it pro­vides a stiff and extremely durable enclosure.

TM

throat

The cabinet includes integral carrying
handles and a stand socket for mounting on

3

1

/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 cabi­net, 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-band­width, 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 high­frequency performance. The voice coil is
coupled to the diaphragm with EV’s exclu­sive Resonant Drive™ Technology. This in­creases and smooths the high-frequency re­sponse and reduces the amount of internal
equalization required for flat frequency re­sponse, 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 vented­horn 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 profes­sional-quality components, arranged in an
unusually durable Thiele-Small-aligned
vented enclosure. The result is clear and ar­ticulate, high-quality sound.

Ring-Mode Decoupling (RMDTM)
Technology

The Sx500+ controls both acoustical and me­chanical ring modes to provide dramatically
increased intelligibility, using techniques
learned from the development of the Electro­Voice X-Array™ concert speakers. There is
much less coloration of the sound from reso­nating 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

Sx500+ 400- Watt Tw o- Way Speaker System

the woofer grille.

Speaker Protection

The Sx500+ like all other vented systems ex­periences rapidly increasing cone excursion
below the box-tuning frequency, while the
acoustic output decreases rapidly. To ensure
a long woofer life even when used at high
power levels, it is recommended that some
form of electronics be used to control un­necessary woofer cone excursion.

Graphic equalizers and active crossovers are
two methods that can be used to prevent low­frequency signal below band-pass from go­ing to the loudspeaker. When using an ac­tive crossover, a high-pass filter with a cut­off frequency of 32- to 45-Hz will provide
the necessary protection. The filter should
have a slope of at least 12 dB per octave.
Such subpass band filters are found in many
crossovers and equalizers manufactured by

Sx500+ 400-Watt Two-Way Speaker System

Electro-V oice, as well as other commercially
available equipment.

Enclosure Construction

The Sx500+ enclosure is contructed of very
durable structural foam that is hard to dent,
scratch or break. The structural foam enclo­sure allows for the high- and low-frequency
horns, the stand mount and the suspension
points to be molded into the enclosure. It also
allows for three handles to be integrated into
the enclosure.

Frequency Response

The combination of a 15-inch woofer, wide­bandwidth high-frequency driver and an
equalized crossover results in the wide and
smooth overall response shown in Figure 1.
This response was measured at 3.05 meters
(10 feet), using a 4-volt swept sine-wave in­put in an anechoic chamber using the inter­nal passive crossover. No external equaliza­tion was used. Figure 1 has been averaged
and corrected for 1 watt at 1 meter.

Connections and Biamping

The Sx500+ is equipped with two parallel
Neutrik Speakon

®

NL4MP connectors. In the
full-range mode, as supplied by the factory,
pins 1+ and 1– are the inputs to the system.

Another system can be connected in parallel

by using the other connector. Care must be
taken not to abuse the amplifier by connect­ing impedances which are too low.

The user may put the system in biamp mode
by removing the input panel and moving a
connector from the full-range mode to biamp
mode, as noted on the crossover. In biamp
mode, 1+, 1– are the LF inputs and 2+, 2–
are the HF inputs.

Constant-Directivity Speaker System

The crossover frequency and speaker- com­ponent geometries have been selected so that
the directional characteristics of the woofer
and constant-directivity high-frequency horn
match at the crossover frequency to create a
special system type — the constant-direc­tivity system. At higher frequencies, the hori­zontal coverage pattern remains constant and
the vertical pattern smoothly transitions to a
60° angle above 5,000 Hz. Response within
the 75° x 60° rated coverage angle is uni­form, which means dependable audience
coverage without “hot spots” or dead zones
at certain frequencies. The 75° x 60° disper­sion characteristic also helps avoid early re­flections from nearby floor or side-wall sur­faces which could degrade performance. The
controlled directivity of the high- and low­frequency transducers also eliminates re­sponse irregularities caused by diffraction off
nearby enclosure edges and, in combination
with an essentially flat on-axis frequency
response, produces a total acoustic power
output that is uniform with frequency.

Directivity

A unique feature of the Sx500+ is the con­stant-directivity dispersion provided by the
75° x 60° horn. The polar response of the
system at selected one-third-octave band­widths is shown in Figure 2. These polar re­sponses were measured in an anechoic envi­ronment at 6.1 meters (20 feet) using one­third-octave pink-noise inputs. The frequen­cies selected are fully representative of the
polar response of the system. Beamwidth of
the system utilizing the complete one-third­octave polar data is shown in Figure 3. Di­rectivity factor, R

and directivity index, Di,

,

are plotted in Figure 4.

Power-Handling Capacity

The Sx500+ is shipped in full-range mode
using an internal crossover. In biamp mode,
the long-term average power-handling ca­pacity is as follows:

Low Frequency: 400 watts
High Frequency: 60 watts

Electro-Voice components and systems are
manufactured to exacting standards, ensur­ing they will hold up, not only through the
most rigorous of power tests, but also
through continued use in arduous, real-life
conditions. The EIA Loudspeaker Power
Rating Full Range (ANSI/EIA RS-426-A

1980) uses a noise spectrum which mimics
typical music and tests the thermal and me­chanical capabilities of the components.
Electro-Voice will support relevant addi­tional standards as and when they become
available. Extreme, in-house power tests,
which push the performance boundaries of
the woofers, are also performed and passed
to ensure years of trouble-free service.

Specifically, the Sx500+ passes ANSI/EIA
RS-426-A 1980 with the following values:

R = 5.76 ohms (1.15 x (R

= woofer DCR

R

E

+ 1.86))

E

1.86 =horn-load impedance correction
= 400 watts

P

E(MAX)

Test voltage = 48.00 volts rms,

96.00 volts peak (+6 dB)

The “peak” power-handling capacity of a
woofer is determined by the peak test-volt­age amount. For the Sx500+, a 96.00-volt
peak test-voltage translates into 1,600-watts
short-term peak power-handling capacity.
This is the equivalent of four times the “av­erage” power-handling capacity, and is a
peak that can be sustained for only a few mil­liseconds. However, this sort of short dura­tion peak is very typical in speech and mu­sic. Provided the amplifier can reproduce the
signal accurately without clipping, the
woofer will also perform accurately and
reliably, even at these levels.

Amplifier Power Recommendations

As noted in the Power-Handling Capacity sec­tion above, the Sx500+ has a random-noise power

2

Sx500+ 400- Watt Tw o- Way Speaker System

capacity of 400-watts long term (1,600- watts
peak) per ANSI/EIA RS-426-A 1980. The fol­lowing guidelines will help relate this to an ap­propriate power amplifier output rating.

1. To use the Sx500+ to full capacity , skilled
experts in sound-system installation and
operation will obtain the best results if
the power amplifier is 2.0 to 4.0 times
the long-term average noise- power rat­ing of the speaker system. For the
Sx500+, this is 800 to 1,600 watts.

The caution cannot be made strongly
enough, however, that this arrangement
is only for experts or those who can disci­pline themselves against “pushing” the
system for ever-higher sound levels and
who can avoid “accidents” such as cata­strophic feedback or dropped micro­phones.

2. A more conservative, “normal” amplifier
size, which will produce audible results
nearly equal to those of the “expert” rec­ommendation, is 1.0 to 1.4 times the long­term average noise-power rating of the
speaker. For the Sx500+, this is 400 to
640 watts.

3. To be very conservative, one can use an
amplifier rated at 0.5 to 0.7 times the
long-term average noise-power rating of
the speaker. For the Sx500+, this is 200
to 280 watts.

Request P.A. Bible Addition No. Two
(“Power Handling Capacity”) for more back­ground on these recommendations.

Service

In the unlikely event the Sx500+ requires ser­vice, the woofer can be removed from the
front. The high-frequency driver can be re­moved from the rear by first removing the
input panel. A service data sheet is available
from Electro-Voice.

Stand Mounting

When used on a stand, the stand must be
placed on a stable surface. The stand must
be rated to support systems of 38.6 kg
(85 lb) or greater. It must have a base diam­eter of 1.22 m (4 ft) or greater. The bottom of
the speaker should be no higher than 1.52 m
(5 ft) from the bottom of the stand. The user

3

must be sure that safe use on a stand is not
affected by wind or any other conditions.

The Sx500+ can be mounted on the 100BK
speaker stand or any other stand with a

3

1

/8-inch diameter shaft.

Suspending Sx500+ Enclosures
WARNING: Suspending any object is

potentially dangerous and should be
attempted only by individuals who have a
thorough knowledge of the techniques and
regulations of rigging objects overhead.
Electro-Voice strongly recommends that
the Sx500+ be suspended taking into
account all current national, federal, state
and local regulations. It is the responsi­bility of the installer to ensure the Sx500+
is safely installed in accordance with all
such regulations. If the Sx500+ is
suspended, Electro-Voice strongly
recommends that the system be inspected
at least once a year . If any sign of weakness
or damage is detected, remedial action
should be taken immediately.

The Sx500+ enclosure contains eight
M8 x 1.25 inserts (see Figure 7) which are
built into the enclosure for the purpose of
suspension. Before the enclosure is sus­pended, these inserts are used to attach plates
that hold the two halves of the enclosure to­gether in addition to providing a way to sus­pend the enclosure.

The suspension kits that are available for the
Sx500+ are listed below. Please refer to in­dividual suspension-kit engineering data
sheets for full details and safety information.

The first approach is to suspend individual
Sx500+ enclosures. The Mb700 forged eye­bolt attachment kit (see Figure 9) is an eye­bolt suspension kit. It includes a top and bot­tom mounting plate to secure the two halves
of the enclosure, in addition to the necessary
hardware. Typically it will be necessary to
attach two cables to the top eyebolts and to
“pull-up” on the bottom plate. The Mb500
wall/ceiling mounting bracket (see Figure 8)
encompasses the top and bottom of the en­closure with a bracket attached to the two
plates to secure the halves of the enclosure.
Additionally, it has features to make suspend­ing the Sx500+ easier and more flexible.
Electro-Voice recommends the use of the

Mb500 in all but the simplest situations. The
Mb500 has supplementary holes to allow the
Sx500+ to be attached to a wall or ceiling
and aimed at an audience.

The second approach is to suspend multiple
Sx500+ enclosures. The Sx500+ enclosure
is not designed to suspend multiple enclo­sures from itself. If an “array” is required,
then multiple Mb500’s must be used. Arrays
may be constructed vertically by “daisy
chaining” two Mb500’s from each other . The
Mb600 horizontal array kit allows the easy
and secure construction of horizontal arrays,
using Mb500’s to support the enclosure.

Architects’ and Engineers’
Specifications

The loudspeaker shall be a compact vented­box type. The low frequencies shall be re­produced with one horn-loaded DL15SX
381-mm (15-in.) woofer. The high frequen­cies shall be reproduced by a DH2T, high­frequency compression driver with a pure­titanium diaphragm, coupled to a
75° x 60° constant-directivity horn molded
into the front baffle of the enclosure. The
system will use a passive crossover-equal­izer network with protection for the high­frequency driver. The loudspeaker shall meet
the following performance criteria: fre­quency response of 60-16,000 Hz, –3 dB;
power handling of 400-watts long term and
1,600-watts short term, with a shaped ran­dom-noise input per ANSI/EIA RS-426-A
1980; sensitivity of 100-dB SPL at 1 meter
with a 1-watt, 300-2,000-Hz pink-noise in­put; 6-dB-down horizontal coverage angle
of 75° + 14°/– 20° in the 2,000- to 20,000­Hz range; 6-dB-down vertical coverage
angle of 60° + 11°/– 8° in the 2,000- to
20,000-Hz range; crossover frequency of
1,600 Hz; nominal impedance of 8 ohms and
minimum impedance of 5.2 ohms in full­range mode. Paralleled input and output con­nectors shall be present, consisting of Neu­trik Speakon

®

NL4MP connectors. The en­closure shall be constructed of polypropylene
structural foam and fitted with a powder­coated steel grille, three integral handles, a
stand socket for mounting on

3

1

/8 -inch stands, rubber feet and mating
sockets to facilitate stacking. Dimensions
shall be 838 mm (33 in.) high x 673 mm

Sx500+ 400-Watt Two-Way Speaker System