Electro-Voice EVX-180B User manual

EVX-180B
18-Inch Low-Frequency
Reproducer
• Exceptionally resistant to long-
term failure in real-world low-bass
applications
• Utilizes findings about failure
modes not revealed in normal
high-power testing
• 1,000 watts continuous program
• Advanced, HeatWickTM design
“wicks” away heat from the voice
coil
• Long, 4-inch voice coil has nearly
twice the surface area of any other
woofer, virtually eliminating power
compression
• Ribbed, Kevlar®fiber composite
cone resists collapse1
Description
The EVX-180B low-frequency transducer is
designed for professional sound reinforce-
ment or studio monitoring applications that
requiremaximumoutputwithlowdistortion.
The EVX-180B woofer provides unprec-
edented power capacity, linearity and excur-
sion, made possible by the HeatWickTM to-
tal-thermal-engineering design. The propri-
etaryHeatWick design actually “wicks” heat
away from the voice coil, significantly in-
creasing power handling and long-term reli-
ability. A special frame extension and elon-
gatedpolepiece provide a metal surface with
close proximity to the entire length of the
voice coil, providing a major heat-transfer
path. Also, the 100-mm (4-in.) diameter
voice coil is longer than conventional me-
dium-efficiency woofers to give additional
power handling and virtually eliminate dy-
namic-range power compression.
Additionally, a Flux Demodulation Device
(FDDTM)reducesdistortioninthecriticalmid
band by providing a “short circuit” effect to
prevent amplifier-signal modulation of the
static magnetic field.
A ribbed, Kevlar®fiber composite cone with
an extremely high stiffness-to-weight
ratio and exceptional strength gives the
EVX-180B increased resistance to cone col-
lapse and deformation, without sacrificing
efficiency.1A rubber mounting flange
gasket provides a reusable seal for front or
rear mounting, completely surrounding the
frame flange.
Directional Performance
The directional characteristics of the
EVX-180B in the TL3512 256-liter (9-ft3)
vented enclosure were measured by running
a set of polar responses in EV’s large
anechoic chamber. The test signal was oc-
tave-band-limitedpseudo-randompinknoise
centered at the ISO standard frequencies.
The curves show horizontal (side-to-side)
dispersion when the enclosure’s long axis is
vertical. The vertical (up-and-down) polar
responsesdeviateonlyslightlyfromthehori-
zontal responses due to box geometry. Typi-
caldata is provided in Figures 3 and 4, which
indicate 6-dB-down beamwidth versus fre-
quency and directivity factor, respectively,
for an EVX-180B in the TL3512 enclosure.
Power-Handling Test
To our knowledge, Electro-Voice was the
first U.S. manufacturer to develop and pub-
lish a power test closely related to real-life
conditions. First, we use a random noise in-
put signal because it contains many frequen-
cies simultaneously, just like real voice or
instrument program. Second, our signal con-
tains more energy at extremely high and low
frequenciesthantypicalactualprogram,add-
ing an extra measure of reliability. Third, the
test signal includes not only the overall
“long-termaverage”or“continuous”level—
which our ears interpret as loudness—but
also short-duration peaks which are many
times higher than the average, just like ac-
tual program. The long-term average level
stresses the speaker thermally (heat). The
instantaneouspeaks test mechanical reliabil-
ity (cone and diaphragm excursion).
Specifically, the EVX-180B is designed to
withstand the power test described in EIA
Standard RS-426A. The EIA test spectrum
isapplied for eight hours. Toobtain the spec-
trum, the output of a white-noise generator
(white noise is a particular type of random
__________
1. Kevlar®is a registered trademarks of DuPont.

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
2
crest factor. This procedure provides a rig-
orous test of both thermal and mechanical
failure modes.
The EVX-180B has also been power tested
with a two-hour sine wave at minimum im-
pedance so that competitive comparisions
can be made using consistent methods. Con-
tinuous program power is defined as 3 dB
above (double) the continuous sine-wave
power rating.
Recommended Enclosures
The most extended bass, lowest distortion
and best control is usually realized in prop-
erly designed vented enclosures. In such de-
signs, the vent, or port, actually provides the
lowest octave of output. The vent is driven
to full acoustic output by a relatively small
motion of the speaker cone itself, acting
through the air contained within the enclo-
sure. The excursion of the EVX-180B at
thesefrequencies is much reduced compared
to sealed or open-back enclosures, directly
reducing harmonic distortion and the possi-
bility of speaker “bottoming.” Several spe-
cific vented-enclosure recommendations are
shown on the following pages. Alternate
tunings are given so that designers can tailor
the low-frequency response to their specific
needs. Figure 5 shows the maximum long-
term SPL versus frequency. The maximum
output is limited by either: (1) the long-term
thermal power-handling capacity or (2) the
speaker’s maximum cone-excursion capabil-
ity,whicheveroccursfirst.Also provided are
recommended enclosures for multiple driver
configurations.
Step-Down Operation
For extra-low bass use, the vent area can be
reduced by one-half, thereby tuning the en-
closure to the “step-down” mode. In step-
down, the tuning frequency is reduced by
half an octave (a factor of 0.7). The result-
ing alignment is then equalized for flat re-
sponse. This procedure results in one-half-
octave lower bass.
Architects’ and Engineers’
Specifications
The low-frequency transducer shall have a
nominal diameter of 460 mm (18 in.), over-
all depth not greater than 198 mm (7.92 in.),
and weigh no more than 11 kg (25 lb). The
frame shall be made of die-cast aluminum to
resist deformation. The magnetic assembly
shall have an extended pole piece to reduce
inductive variances with excursion, and pro-
vide a symmetrical magnetic field at the
voice-coil gap. Two aluminum rings shall
encircle the pole piece above and below the
magnetic gap, and shall have internal diam-
eters concentric with the internal diameter
of the steel top plate. The upper ring shall be
part of the loudspeaker frame. Both rings act
toreducefluxmodulationandprovideaheat-
transfer path from the outer diameter of the
voice coil.
The voice coil shall be 100 mm (4 in.) in
diameter and 20 mm (0.8 in.) in winding
length, and shall be made of edge-wound
aluminum ribbon. When centered in the
magnetic gap, the voice coil shall produce a
force of not less than 21.9 newtons (tesla-
ampere-meters)withadccurrentof 1 ampere.
Performance specifications of a typical pro-
duction unit shall be as follows: measured
sensitivity (SPL at 1 m (3.3 ft) with 1-watt
input, 100- to 800-Hz pink noise) shall be at
least 96 dB. The half-space reference effi-
ciency shall be at least 3.0%. The usable fre-
quency response shall be 20 Hz to 2,000 Hz,
and the nominal impedance shall be 8 ohms.
The rated power for the loudspeaker shall
be 1,000 watts continuous program power.
The low-frequency transducer shall be the
Electro-Voice EVX-180B.
AES Specifications
EVX-180B specifications are in accordance
with the “AES Recommended Practice for
Specification of Components Used in Pro-
fessional Audio and Sound Reinforcement”
(AES2-1984; ANSI S4.26-1984).
Mounting
The EVX-180B may be front or rear
mountedagainst either surface of the mount-
ing flange and requires a 422-mm (16.6-in.)
diameter cutout and a 441-mm (17.38-in.)
bolt circle. Normal fasteners up to 6 mm (¼
in.) will fit through the eight holes in the
frame. Front mounting is simplest using the
optionalSMH-1speaker mounting hardware.
Electrical Connections
The EVX-180B is fitted with a pair of
chrome-plated, frame-mounted connectors
withcolor-coded ends. Electrical connection
is made by pushing down, inserting wire
completely through the rectangular slot and
releasing pressure. One conductor of #9
AWG stranded, #8 AWG solid, a pair of
twisted #15 AWG stranded or a pair of #14
AWG solid conductors will fit. A positive
electrical signal applied to the red (+) termi-
nal will displace the cone away from the
magnet, thus producing a positive acoustic
pressure.
Multiple-Driver Applications
Whenusedinarraysandmultiple-driverbass
boxes, the system Thiele-Small parameters
can be synthesized as follows. This data
should be used for multiple-driver configu-
rations.
Two Drivers:
fs:28.1 Hz
Qts:0.275
Vas:835 liters (29.5 ft3)
Four Drivers:
fs:26.9 Hz
Qts:0.286
Vas:1,671 liters (59.0 ft3)
Designers will find the following equation
useful in tuning their enclosures:
SV
LV = ———————————— – K r
3.7 x 10–4 VBfB2
Where:
Lv= Length of vent in inches or thick
ness of baffle for hole in baffle
SV= Area of vent in square inches
VB= Volume of box in cubic feet
fB= Box tuning in Hz
r = Radius of vent
K = 1.7 for a hole in baffle, 1.5 for a
tube in inches

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
3
Limited warranty
Electro-Voice products are guaranteed
against malfunction due to defects in mate-
rials or workmanship for a specified period,
as noted in the individual product-line
statement(s)below, or in theindividualprod-
uct data sheet or owner’s manual, beginning
with the date of original purchase. If such
malfunction occurs during the specified pe-
riod, the product will be repaired or replaced
(at our option) without charge. The product
will be returned to the customer prepaid.
Exclusions and Limitations: The Limited
Warranty does not apply to: (a) exterior fin-
ish or appearance; (b) certain specific items
described in the individual product-line
statement(s)below, or in theindividualprod-
uct data sheet or owner’s manual; (c) mal-
function resulting from use or operation of
the product other than as specified in the
product data sheet or owner’s manual; (d)
malfunction resulting from misuse or abuse
of the product; or (e) malfunction occurring
at any time after repairs have been made to
the product by anyone other than Electro-
Voice or any of its authorized service repre-
sentatives. Obtaining Warranty Service:
To obtain warranty service, a customer must
delivertheproduct,prepaid,toElectro-Voice
or any of its authorized service representa-
tives together with proof of purchase of the
product in the form of a bill of sale or re-
ceipted invoice. A list of authorized service
representatives is available from Electro-
Voice at 600 Cecil Street, Buchanan, MI
49107 (616/695-6831). Incidental and
Consequential Damages Excluded: Prod-
uct repair or replacement and return to the
customer are the only remedies provided to
the customer. Electro-Voice shall not be li-
ableforanyincidentalor consequential dam-
ages including, without limitation, injury to
persons or property or loss of use. Some
states do not allow the exclusion or limita-
tion of incidental or consequential damages
so the above limitation or exclusion may not
apply to you. Other Rights: This warranty
gives you specific legal rights, and you may
also have other rights which vary from state
to state.
Electro-Voice Speakers and Speaker Sys-
temsare guaranteedagainst malfunction due
to defects in materials or workmanship for a
periodoffive(5)yearsfromthedateoforigi-
nalpurchase.TheLimitedWarranty does not
apply to burned voice coils or malfunctions
such as cone and/or coil damage resulting
from improperly designed enclosures. Elec-
tro-Voice active electronics associated with
the speaker systems are guaranteed for three
(3) years from the date of original purchase.
Additional details are included in the Uni-
form Limited Warranty statement.
Service and repair address for this product:
Electro-Voice, Inc., 600 Cecil Street, Bucha-
nan, Michigan 49107.
Specifications subject to change without
notice.
Figure 1—Axial Frequency Response, 1
Watt/1 Meter, 10-Cubic-Foot Enclosure
Figure 2A—EVX-180B Single-Driver
Low-Frequency Performance in 170-
Liter (6-ft3) Enclosure

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
4
Figure 2B—EVX-180B Single-
Driver Low-Frequency
Performance in
227-Liter (8-ft3) Enclosure
Figure 2C—EVX-180B Single-
Driver Low-Frequency
Performance in
283-Liter (10-ft3) Enclosure
Figure 2D—EVX-180B Multiple-
Driver Low-Frequency
Performance,
Two Drivers in a 566-Liter (20-ft3)
Box or Two 283-Liter (10-ft3) Boxes
in Close Proximity Tuned to 30 Hz
Figure 2E—EVX-180B Multiple-
Driver Low-Frequency
Performance,
Four Drivers in a 1,132-Liter (40-
ft3) Box or Four 566-Liter (20-ft3)
Boxes in Close Proximity Tuned to
28 Hz

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
5
Figure 3—Beamwidth vs. Frequency
EVX-180B (TL3512) in a 255-Liter
(9.0-ft3) Enclosure
Figure 5 —Theoretical Low-Frequency
Maximum SPL vs. Frequency, 227-Liter
(8-ft3) Enclosure Tuned to 35 Hz
Figure 4—Directivity Index vs. Frequency
Figure 6—Polar Response

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
6
Figure 7—Distortion Response, 6 Watts
Figure 8—Distortion Response,
60 Watts
Figure 9—Response in Standard Baffle
FREQUENCY IN HERTZ
FREQUENCY IN HERTZ
5 dB
RESPONSE IN dB RESPONSE IN dB 5 dB
IMPEDANCE IN OHMS
FREQUENCY IN HERTZ

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
7
Figure 10—Impedance Response
(EVX-180B)
FREQUENCY IN HERTZ
RESPONSE IN dB 5 dB

EVX-180B 18-Inch Low-Frequency Reproducer
EVX-180B 18-Inch Low-Frequency Reproducer
8
600 Cecil Street, Buchanan, MI 49107
616/695-6831, 616/695-1304 Fax
TRANSDUCER-Low-frequency Part Number 534954-A — 9905
600 Cecil Street, Buchanan, MI 49107
616/695-6831, 616/695-1304 Fax
©Telex Communications, Inc. 1999 • Litho in U.S.A.
Specifications
Power Handling (see Power-Handling
Test section):
1,000 watts continuous program
Voice-Coil Diameter:
102 mm (4.0 in.)
Sensitivity (SPL at 1 W/1 m), 100-800-Hz
average):
98 dB
Impedance,
Nominal:
8 ohms
Minimum:
7 ohms
Frequency Response (see Figure 1, 2 and
10):
20-2,000 Hz
Highest Recommended Crossover:
500 Hz
Magnet Assembly Weight:
8.3 kg (18.3 lb)
Physical Constants,
Effective Piston Diameter:
394 mm (15.5 in.)
Total Moving Mass:
0.127 kg (0.280 lb)
Voice-Coil Winding Depth:
20.3 mm (0.80 in.)
Top-Plate Thickness at Voice Coil:
8.9 mm (0.35 in.)
BL Factor:
21.9 tesla-meters
Thiele-Small Parameters,
fs:29 Hz
VAS:416 liters (14.7 ft3)
QES:0.285
QMS:4.00
QTS:0.266
RE:5.0 ohms
ηη
ηη
η
O
:3.42%
SD:0.122 m2(189 in.2)
MMD:0.127 kg (0.280 lb)
LE:
CMS:0.200 mm/N
RMS:6.86 mechanical ohms
PE(max):600 watts
xmax1:6.4 mm (0.25 in.)
Xlim2:25 mm (0.98 in.)
Thermal Rise after Power Test:
82° C (147° F)
Typical Vented Enclosures (see Recom
mended Enclosures section):
170-283 liters (6-10 ft3) tuned from
28 Hz to 45 Hz
Electrical Connections (see Electrical
Connections section),
Connector Type:
Push terminals for bare wires
Polarity:
A positive voltage applied to the
positive (red) terminal produces a
positive pressure at the front of the
cone
Additional Descriptive Information,
Magnet Weight:
2.2 kg (4.9 lb)
1. Xmax is the one-way peak excursion that produces 10% distortion of the current waveform when driven at fs.
2. Xlim, or displacement limit, is the one-way peak excursion which, when exceeded, will cause physical damage to the drive mechanisum.
Magnet Material:
Barium ferrite
Frame:
Cast aluminum
Frame finish:
Voice-Coil Material:
Aluminum
Voice-Coil Insulation:
Polyimide, 220° C (428° F) rating
Voice-Coil Form:
Polyimide
Plating of Steel Parts:
E-coat (XXX???)
Dimensions,
Outer Diameter:
460 mm (18.2 in.)
Depth:
200 mm (7.92 in.)
Bolt-Hole Diameter:
7.1 mm (0.281 in.)
Net Weight:
11.3 kg (25 lb)
Shipping Weight:
14.1 kg (31 lb)