Electro-Voice S12 User manual

S12
Two-Way Stage Speaker
System
•PROTM circuit provides HF driver
protection
•Integral stand mount
•Constant-directivity 60° x 40°
horn
•250-watt long-term RMS power
capacity
•Roadworthy enclosure with metal
corners, a metal grille and a
durable black carpet finish
•Dual 1/4-inch phone jack or Dual
Neutrik Speakon®inputs 1
____________________________________
1See Connections section
Description
The Electro-Voice S12 is a 250-watt, two-
way, high-efficiency, constant directivity
stage system featuring a vented, direct-radi-
ating woofer section. It combines profes-
sional quality Electro-Voice components in
anunusuallydurable,light-weightenclosure.
The result is wide-range accurate sound re-
production with transparent highs and ex-
tended bass response.
The high-frequency section of the S12 uti-
lizes a 60° X 40° constant-directivity horn
drivenbyaone-inchthroat,wide-bandwidth,
titanium-diaphragm driver. The DH2010A
uses a unique, convex-drive Time PathTM
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 DriveTM Technology. This in-
creases and smooths the high-frequency re-
sponse and reduces the amount of internal
equalization required for flat frequency re-
sponse. Driver output extends to 20,000 Hz.
A self-resetting high-frequency protection
circuit, EV’s PROTM circuit, is included with
the S12 to prevent against accidental over-
drive and improve system reliability. If the
input power to the high-frequency driver
exceeds the nominal rating, the protection
circuitis activated and reduces the power de-
livered 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 S12 is designed us-
ing Thiele-Small parameters for solid per-
formance to 53 Hz. The 305-mm (12-in.)
SG12 woofer used is a specially designed
unit featuring an extended length voice coil
andhigh-temperatureconstructionmaterials.
The system combines professional-quality
components, arranged in an unusually du-
rableThiele-Small-alignedventedenclosure.
The result is clear and articulate, high-qual-
ity sound.
Speaker Protection
The S12, like all other vented systems, ex-
periences rapidly increasing cone excursion
below the box-tuning frequency, while the
acousticoutputdecreasesrapidly. Therefore,
to protect the S12 and maximize the power
output of the system, it is necessary to insert
an active 32- to 45-Hz high-pass filter into
the circuit. The filter should have a slope of
at least 12 dB per octave. Such subpassband
filters are found in many crossovers and
equalizers manufactured by Electro-Voice,
as well as other commercially available
equipment.
Enclosure Construction
The S12 enclosure is constructed of Road-
WoodTM, a structural material that combines
thestrengthofhigh-qualityplywoodwiththe
density and acoustic damping of particle
board without brittleness. Road-WoodTM
uses the same principle of crossbanding ve-
neers, as in plywood, in order to achieve its
very high rigidity. A tough liquid-phenolic
resin is blended with long, narrow strands
of hard-wood. Alternate layers are perpen-
dicularlybondedunderintenseheatandpres-
sure to form panels of superior uniformity.
Unlike many grades of plywood, Road-
WoodTM isdimensionallystable,water-resis-
tant and free from voids.
A combination of dado cut joints and tough
adhesives ensure a sonically dead enclosure
free from panel resonances.
Thedensely-woven, industrial-grade, abuse-
resistant carpeting provides a finish that is
both attractive and highly durable. Heavy-
duty metal corner protectors, firmly secured
rubber feet, recessed handles and a protec-
tive metal grille complete the picture and

S12Two-WayStageSpeakerSystem
S12Two-WayStageSpeakerSystem
ensure that the S12 speaker system is ide-
ally suited to a long and reliable life on the
road.
Frequency Response
The combination of a 12-inch woofer, wide-
bandwidth 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 in-
put in an anechoic chamber. No external
equalization was used. Figure 1 has been
averaged and corrected for 1 watt at 1 meter.
Connections
The S12 is equipped with two parallel
1/4-inch phone jacks. (The S12-E has two
parallel Neutrik Speakon®NL4MP connec-
tors.) 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.
Constant-Directivity Speaker System
The crossover frequency and speaker com-
ponentgeometries have been selected so that
the directional characteristics of the woofer
and constant-directivity horn match at the
crossover frequency to create a special sys-
tem type — the constant-directivity system.
Athigherfrequenciesthehorizontalcoverage
pattern remains constant and the vertical pat-
ternsmoothly transitions to a 40° angle above
5,000Hz. Responsewithinthe60°x40° rated
coverage angle is uniform, which means de-
pendable audience coverage without “hot
spots” or dead zones at certain frequencies.
The 60° x 40° dispersion characteristic also
helps avoid early reflections from nearby
floor or side-wall surfaces which could de-
grade performance. The controlled directiv-
ity of the high- and low-frequency transduc-
ers also eliminates response irregularities
caused by diffraction off nearby enclosure
edgesand,incombinationwithanessentially
flat on-axis frequency response, produces a
total acoustic power output that is uniform
with frequency.
Directivity
A unique feature of the S12 is the con-
stant-directivity dispersion provided by
the 60° x 40° horn. The polar response of
thesystematselectedone-third-octaveband-
widths is shown in Figure 5. These polar
responses were measured in an anechoic en-
vironment at 6.1 meters (20 feet) using one-
third-octavepink-noise inputs. The frequen-
cies selected are fully representative of the
polar response of the system. Beamwidth
of the system utilizing the complete one-
third-octave polar data is shown in Figure 6.
Directivity factor, Rθ, and directivity index,
Di, are plotted in Figure 7.
Power-Handling Capacity
Electro-Voice components and systems are
manufactured to exacting standards, ensur-
ing 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 me-
chanical capabilities of the components.
Electro-Voice will support relevant addi-
tional 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 S12 passes ANSI/EIA
RS-426-A 1980 with the following values:
RSR = 5.98 ohms (1.15 x RE)
PE(MAX) = 250 watts
Test voltage = 38.67 volts rms,
77.33 volts peak (+6dB)
The “peak” power-handling capacity of a
woofer is determined by the peak test volt-
age amount. For the S12, a 77.33-volt peak
testvoltagetranslatesinto1,000-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 accu-
rately, without clipping, the system will per-
form accurately and reliably, even at these
levels.
Amplifier Power Recommendations
Asnoted inthePower-Handling Capacitysec-
tion,above, theS12has arandom-noisepower
capacity of 250 watts long term (1,000 watts
peak) per ANSI/EIA RS-426-A 1980. The
following guidelines will help relate this to
an appropriate power amplifier output rat-
ing.
1. To use the S12 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 rat-
ing of the speaker system. For the S12
this is 500 to 1,000 watts.
The caution cannot be made strongly
enough, however, that this arrange-
ment is only for experts or those who
can discipline themselves against
“pushing” the system for ever-higher
sound levels and who can avoid “acci-
dents” 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” rec-
ommendation, is 1.0 to 1.4 times the
long-term average noise power rating of
the speaker. For the S12 this is 250 to
350 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 loudspeaker. For the S12 this is 125
to 175 watts.
Request P.A. Bible Addition No. Two
(“PowerHandlingCapacity”)formoreback-
ground on these recommendations.
Service
In the unlikely event the S12 requires ser-
vice, the woofer and driver can both be re-
placed or serviced from the front. A service
data sheet is available from Electro-Voice.
Stand Mounting
The S12 can be mounted on the 100BK
speaker stand, or any other stand with
a 1-3/8-inch diameter shaft.

S12Two-Way StageSpeaker System
S12Two-WayStageSpeakerSystem
Architects' and Engineers'
Specifications
The loudspeaker shall be a compact vented-
box type. The low frequencies shall be re-
producedwith one 250-watt (ANSI/EIA RS-
426-A 1980) SG12 305-mm (12-in.) vented
woofer, and a DH2010A high-frequency
compression driver mounted on a 60° X 40°
constant-directivity horn. The system will
reproducethe frequencies from53to 20,000 Hz.
The system shall be capable of producing
average sound levels in excess of 121 dB in the
long term, and short-term peaks of 127 dB.
The enclosure shall be constructed of black-
carpeted Road-WoodTM and have a metal
grille which attaches with 7 screws. The
dimensions shall be 727 mm (28.7 in.) tall,
429 mm (16.9 in.) wide, and 403 mm (15.9 in.)
deep. Thesystemshall weigh 22.7 kg (50 lb).
Two parallel 1/4-inch phone jack connec-
tions shall be provided. (Two Neutrik
Speakon®connections shall be provided on
the “E” version.)
The loudspeaker system shall be the Elec-
tro-Voice S12 (or S12-E).
Uniform 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 the individual prod-
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 the individual prod-
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 Mark IV
Audio Service or any of its authorized ser-
vice representatives. Obtaining Warranty
Service: To obtain warranty service, a cus-
tomer must deliver the product, prepaid, to
Mark IV Audio Service or any of its autho-
rized service representatives together with
proof of purchase of the product in the form
of a bill of sale or receipted invoice. A list
ofauthorizedservicerepresentativesisavail-
able from Mark IV Audio Service at 600
Cecil Street, Buchanan, MI 49107 (800/234/
6831 or FAX [phone]). Incidental
and Consequential Damages Excluded:
Product repair or replacement and return to
the customer are the only remedies provided
to the customer. Electro-Voice shall not be
liable for any incidental or consequential
damages including, without limitation, in-
jury to persons or property or loss of use.
Some states do not allow the exclusion or
limitation of incidental or consequential
damages so the above limitation or exclu-
sion may not apply to you. Other Rights:
Thiswarranty gives you specific legal rights,
and you may also have other rights which
vary from state to state.
Electro-Voice Speakers and Speaker Sys-
temsareguaranteedagainstmalfunction due
to defects in materials or workmanship for a
periodoffive(5)yearsfrom the date of origi-
nalpurchase.The Limited Warrantydoesnot
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.
For warranty repair, service information, or
a listing of the repair facilities nearest you,
contactthe service repair department at: 616/
695-6831 or 800/685-2606.
Fortechnical assistance, contact Technical
Support at 800/234-6831 or 616/695-6831,
M-F, 8:00 a.m. to 5:00 p.m. eastern standard
time.
Specifications subject to change without no-
tice.
Figure 1—Axial Frequency Response,
(anechoic environment, 4 volts/3.05
meters (10 feet), normalized to 1 watt/1
meter)

S12Two-Way StageSpeaker System
S12Two-WayStageSpeakerSystem
Figure 2—Harmonic Distortion
Response 10% Rated Power Input
(25 watts), (anechoic environment,
3.05 meters (10 feet) on axis)
Figure 3—Impedance Curve
Figure 4—Dimension Line Drawing

S12Two-Way StageSpeaker System
S12Two-WayStageSpeakerSystem
Figure 5—One-Third-Octave Polar
Responses (anechoic environment, 4
volts/6.10 meters (20 feet))
Figure 6—Beamwidth vs. Frequency
(anechoic environment)
HORIZONTAL
VERTICAL

S12Two-WayStageSpeakerSystem
S12Two-WayStageSpeakerSystem
Figure 7—Directivity vs. Frequency
(anechoic environment)
Specifications
Typical Axial Frequency Response,
Swept Sine Wave, 4 volts at 3.05 meters
(10 feet), (anechoic environment,
normalized for 1 watt at 1 meter; see
Figure 1):
68-20,000 Hz
Low-Frequency 3-dB-Down Point:
68 Hz
Usable Low-Frequency Limit (10-dB-
down point):
53 Hz
Efficiency:
2.9%
Long-Term Average Power-Handling
Capacity per EIA Standard RS-426A
(see Power-Handling section):
250 watts
Maximum Woofer Acoustic Output:
7.3 watts
Sensitivity (SPL at 1 watt, 1 meter
input, anechoic environment, swept
sine wave):
97 dB
Dispersion Angle Included by 6-dB-
Down Points on Polar Responses,
Indicated One-Third-Octave Bands of
Pink Noise (see Figure 6),
2,500-20,000 Hz, Horizontal:
60° (+16°, –15°)
2,500-20,000 Hz, Vertical:
40° (+11°, –8°)
Directivity Factor Rθθ
θθ
θ(Q), 800- to
16,000-Hz Median (see Figure 7):
18.2 (+17.5, –13.0)
Directivity Index Di, 800- to 16,000-Hz
Median (see Figure 7):
12.6 dB (+2.9 dB, –5.4 dB)
Distortion, 0.1 Full Power Input,
(see Figure 2)
Second Harmonic,
100 Hz:
–31 dB, 2.9%
1,000 Hz:
–48 dB, 0.4%
10,000 Hz:
–20 dB, 9.8%
Third Harmonic,
100 Hz:
–38 dB, 1.3%
1,000 Hz:
–36 dB, 1.6%
10,000 Hz:
–37 dB, 1.4%
Transducer Complement,
Low-Frequency:
SG12 12-inch woofer
High Frequency:
DH2010A driver
HP64M constant-directivity horn
Box Tuning Frequency:
63 Hz
Crossover Frequency:
3,000 Hz
Crossover Slope:
12 dB per octave
Impedance,
Nominal:
8 ohms
Minimum:
6.8 ohms
Input Connections:
Two parallel 1/4-inch phone jacks
(Two parallel Neutrik Speakon®
NL4MP connectors on S12-E)
Enclosure Materials and Colors:
Black-carpeted Road-WoodTM
Black perforated metal grille
Dimensions (see Figure 4),
Height:
727 mm (28.7 in.)
Width:
429 mm (16.9 in.)
Depth:
403 mm (15.9 in.)
Net Weight:
22.7 kg (50 lb)
Shipping Weight:
25.9 kg (57 lb)
Optional Accessory:
100BK mounting stand
Part Number 533654 – 9639
600 Cecil Street, Buchanan, MI 49107
800/234-6831, 616/695-6831, 616/695-1304 Fax
a MARK IV company
SPEAKERS—Portables