Electro-Voice TL880D User manual

TL880D
Very-Low-Frequency
Speaker System
• Designed for cinema subwoofer use
• High acoustic output to below 20 Hz
• Two EVX-180A woofers provide very
high peak and long-term output that
complements the dynamic potential of
digital sound on film
• 2,000 watts continuous program
• Side-mounted connection panel
facilitates hookup when depth behind
the screen is restricted
• High output ability in the 20- to
40-Hz range is also ideal for
very-low-frequency synthesized
effects, down-tuned bass guitars
or pipe organ
• Approved for subwoofer use in THX®
cinema systems*
Description and Applications
The Electro-Voice TL880D is a member of
the TL series of low-frequency enclosures.
TheTL880Disadualdirect-radiatingvented
design that provides high efficiency, low
distortion and excellent low-frequency
performance. The TL880D employs two
long-throw EVX-180A 18-inch loudspeak-
ers, in an 15.5-ft3, black-finished enclosure
without grille. It is specifically designed to
meet the low-frequency demands of digital
cinema sound, in subwoofer applications.
TheTL880D’shighpumping capability,high
acoustic output ability and extended bass
response (to below 20 Hz) make it par-
ticularly appropriate for the dynamic po-
tentialof the digital cinema application. (The
TL880D is approved for subwoofer use in
THX®cinema systems.)* The side-mounted
input panel facilitates behind-the-screen in-
stallation, where limited space betweenthe
screen and theatre wall often makes it diffi-
cult to connect to the back of an enclosure.
The TL880D’s performance characteristics
also make it highly appropriate as the
subwoofer in large, multiway systems for
contemporary music playback and sound
reinforcement. The TL880D has more out-
put below 40 Hz than the devices typically
used in these applications.
Frequency Response
TheTL880D’saxial frequency response was
measured in Electro-Voice’s large anechoic
chamber at a distance of 10 feet with a swept
sine-wave input of 4 volts. Figure 1 has been
averaged and corrected for 1 watt/1 meter.
Directivity
The directional characteristics of the
TL880D were measured in Electro-Voice’s
large anechoic chamber; the test signal was
one-third-octave filtered pink noise at the
frequencies indicated. A full spherical
measurement system was used, which is
compatible with the AcoustaCADDTM com-
puter-aided design program. All directional
information was measured at 20 feet.
Figure 2 illustrates the horizontal and
vertical polar responses. Figure 3 shows the
horizontal and vertical beamwidths.
Beamwidth is the angle at which the hori-
zontal and vertical polar responses have
decreased in level by 6 dB when compared
to the axial frequency response.
Figure 4 illustrates the total directivity of the
TL880D. The directivity factor Rθ(Q) is the
relative value, at a point, of the TL880D
when compared to an ideal spherical
response. The directivity index, Di, is calcu-
lated by Di= 10 log Rθ.
Power Hanndling Capacity
To our knowledge Electro-Voice was the first
U.S. manufacturer to develop and publish a
power test closely related to real-life condi-
tions. A random noise input signal is used
because it contains many frequencies simul-
taneously, just like real voice or instrument
program. The signal contains more energy
at extremely high and low frequencies than
typical actual program, adding an extra mar-
gin of reliability. The test combines not only
the overall long-term average or continuous
level—which our ear interprets as loud-
ness—but also short-duration peaks which
are many times higher than the average, just
like actual program. The long-term average
level stresses the speaker thermally (heat).
The instantaneous peaks test mechanical re-
liability (cone excursion). Note that the sine-
wave test signals sometimes used have a
much less demanding peak value relative to
their average level. In actual use, long-term
average levels exist from several seconds on
up. We test for several hours, adding an-
other extra level of reliability.
_________________
*THX is a registered trademark of Lucasfilm Ltd.

TL880DVery-Low-FrequencySpeakerSystem
TL880DVery-Low-FrequencySpeakerSystem
Specifically,theTL880D is designed to with-
stand the power test described in ANSI/EIA
RS-426-A 1980. The EIA test spectrum is
applied for eight hours. The spectrum is ob-
tained by filtering white noise (a particular
type of random noise with equal energy per
bandwidth). The filter applies a 6-dB-per-
octaveslope below 40 Hz and above318 Hz.
Whenmeasuredwithaone-third-octavecon-
stant-percentageanalyzer,this filter produces
a spectrum whose 3-dB-down points are at
100 Hz and 1,200 Hz with a 3-dB-per-oc-
tave slope above 1,200 Hz. This shaped sig-
nal is fed to the power amplifier with the
continuous power set to provide 1,200 watts
into the 4.8-ohm EIA equivalent impedance
(75.9 volts rms).
Amplifier clipping sets instantaneous peaks
at6 dB above the continuous power,or 4,800
watts peak (151.8 volts peak). This proce-
dure provides a rigorous test of both ther-
mal and mechanical failure modes.
TheTL880Dhasalsobeenpower tested with
a two-hour sine wave, at minimum imped-
ance, so that competitive comparisons can
be made using consistent methods. Continu-
ous program power is defined as 3 dB above
(double) the continuous sine-wave power
rating.
Subpassband Speaker Protection
Below the enclosure tuning frequency, cone
excursion increases rapidly. Since acoustic
output is also falling rapidly, there is no util-
ity in driving the system with signals much
below tuning frequency. While such signals
may be in the program material, they are of-
ten extraneous, such as a dropped micro-
phone. The Electro-Voice EX-24, XEQ-2
and XEQ-3 electronic crossover/equalizers
can provide the necessary subpassband pro-
tection. The 3-dB-down points are 30 Hz
(EX-24 and XEQ-2) and 16 Hz or 32 Hz
(XEQ-3).
Otherhigh-pass filters are available and one-
third-octave equalizers can also be effective
at providing the required protection.
Use In Multiples
Cone loudspeakers may be stacked for
greater acoustic output and a narrower
beamwidth. (It is assumed that all cones are
operatingin unison or “in phase.”) This prin-
ciple is already employed in the dual-woofer
TL880D, and is responsible for the higher
sensitivity and narrower vertical beamwidth
(with the system long axis vertical) relative
tosimilarsingle-woofersystems.Inaddition,
two TL880D’s can be used side-by-side and
their combined performance will be differ-
ent from that of a single TL880D in the ways
outlined below.
At relatively low frequencies, below about
150 Hz for typical TL series dimensions,
stacking produces additional acoustic out-
putwithoutalteringdispersion.Whena com-
mon signal is applied, a 6-dB increase in
maximum acoustic output occurs. The cones
“mutually couple” and act as one cone with
twicethearea(thereforetwicetheefficiency)
and twice the power capacity. The additional
cone area provides 3 dB more output and
the additional power capacity accounts for
the remaining 3 dB.
Specifically, mutual coupling occurs at fre-
quencies whose wavelengths are longer than
one-quarter the center-to-center distance
between the cones. The highest frequency
at which mutual coupling occurs is calcu-
lated from the following equation:
3,000
f @ ————— ,
DMAX
where DMAX (inches) is the distance between
thecones, and f (Hz) is the highestfrequency
at which coupling occurs. When DMAX is
greater than one-quarter wavelength, which
would occur if two TL880D’s were widely
spaced, or at frequencies much above f even
when closely spaced, the increase in acous-
tic output is limited to the 3-dB power-han-
dling increase.
Installation and Suspension of TL880D
Enclosures
The TL880D is designed for typical cinema
stage(behind-the-screen)applications where
subwoofers are mounted on the stage floor.
TheTL880Dis not designed to beself-sus-
pended from above, and if suspended,
must be supported and hung in a way
which does not depend on the structure
of the TL880D itself for support.
Architects' and Engineers'
Specifications
The loudspeaker system shall be a dual low-
frequency, bass-reflex design. Two 18-inch
woofers shall be front mounted in an 15.5-
ft3enclosure. The system shall meet the fol-
lowing criteria: power handling, 1,200 watts
of pink noise with a 6-dB crest factor; fre-
quency response, smooth and uniform, us-
able at high output levels from 23 to 2,000
Hz; sensitivity, 98 dB at one watt, one meter,
100 to 800 Hz, on axis; impedance (woofers
paralleled), 4 ohms nominal, 4.2 ohms mini-
mum; dispersion angles 220° (horizontal) x
180° (vertical) at 200 Hz. The enclosure
shall be constructed of black texture-painted
poplar plywood . The enclosure will contain
sound-absorbing glass wool. Each woofer
shall have the capacity to be fed indepen-
dently of the other. The input panel and con-
nectors shall be side-mounted. An installed
vent cover shall be supplied that, when re-
moved, shall raise the box tuning frequency
from 25 Hz to 30 Hz, for increased output in
the 30- to 40-Hz range. The enclosure di-
mensions shall be 47.5 in. high x 30.0 in.
wide x 23.8 in. deep (121 cm x 76.2 cm x
60.5 cm). Net weight shall be 160 lb (72.6 kg).
The low-frequency speaker system shall be
the Electro-Voice TL880D.
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 individualprod-
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 individualprod-
uct data sheet or owner’s manual; (c) mal-
function resulting from use or operation of
the product other than as specified in the

TL880DVery-Low-FrequencySpeakerSystem
Bug right
Figure 1—TL880D Axial Frequency
Response (anechoic environment,
1 watt/1 meter)
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 EVI Au-
dio Service or any of its authorized service
representatives. Obtaining Warranty Ser-
vice:To obtain warranty service, a customer
must deliver the product, prepaid, to EVI
Audio Service or any of its authorized ser-
vice representatives together with proof of
purchase of the product in the form of a bill
of sale or receipted invoice. A list of autho-
rizedservice representatives is available from
EVI Audio Service at 600 Cecil Street,
Buchanan,MI 49107 (800/234/6831 or FAX
616/695/4743). Incidental and Conse-
quential Damages Excluded: Product re-
pair or replacement and return to the cus-
tomer are the only remedies provided to the
customer. Electro-Voice shall not be liable
foranyincidental or consequential damages
including, without limitation, injury to per-
sons 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 exclusion may not ap-
ply to you. Other Rights: This warranty
givesyou specific legal rights, and youmay
also have other rights which vary from state
to state.
Electro-Voice Speakersand SpeakerSys-
tems are guaranteed against malfunction
due to defects in materials or workmanship
for a period of five (5) years from the date
of original purchase. The Limited Warranty
does not apply to burned voice coils or mal-
functions such as cone and/or coil damage
resulting from improperly designed enclo-
sures. Electro-Voice active electronics as-
sociated with the speaker systems are guar-
anteed for three (3) years from the date of
original purchase. Additional details are in-
cluded in the Uniform Limited Warranty
statement.
Electro-Voice Electronics are guaranteed
against malfunction due to defects in mate-
rials or workmanship for a period of 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 Stan-
dard time.
Specifications subject to change without no-
tice.

TL880DVery-Low-FrequencySpeakerSystem
TL880DVery-Low-FrequencySpeakerSystem
Figure 2—TL880D One-Third-Octave
Polar Responses (anechoic environment)
HORIZONTAL
VERTICAL

TL880DVery-Low-FrequencySpeakerSystem
TL880DVery-Low-FrequencySpeakerSystem
FIGURE 4—TL880D One-Third-
Octave Directivity vs Frequency
(anechoic environment)
FIGURE 5—TL880D Harmonic
Distortion, 0.1 Rated Power Input
(120 watts), 10 Feet on Axis
FIGURE 3—TL880D One-Third-
Octave Beamwidth vs Frequency
(anechoic environment)

TL880DVery-Low-FrequencySpeakerSystem
TL880DVery-Low-FrequencySpeakerSystem
SPEAKERS—Low-Frequency Systems Part Number 534147—9703
600 Cecil Street, Buchanan, MI 49107
616/695-6831, 616/695-1304 Fax
Specification
Frequency Response, 1 Watt at 1 Meter
on Axis, Swept One-Third-Octave
Pink Noise, Anechoic Environment
(see Figure 1):
23-1,800 Hz
Low-Frequency 3-dB-Down Point:
23 Hz
Usable Low-Frequency Limit (10-dB-
down point),
Normal Tuning:
20 Hz
Half-Space Reference Efficiency:
6.0%
Power-Handling Capacity (see Power
Handling section),
Long-Term Average per ANSI/EIA
RS-426-A 1980:
1,200 watts
Continuous Program:
2,000 watts
Maximum Long-Term Average Mid-
Band Acoustic Output:
72 watts
Sound Pressure Level at 1 Meter, 1 Watt
(2.0 volts) Input, Anechoic Environ-
ment,Band-Limited Pink-Noise
Signal,
100-800 Hz:
98 dB
50-125 Hz:
96 dB
Dispersion Angle Included by 6-dB-
Down Points on Polar Responses,
Indicated One-Third-Octave Bands of
Pink Noise (see Figure 3),
90-125 Hz, Horizontal and Vertical:
360°
125-500 Hz, Horizontal:
200° ± 80°
125-500 Hz, Vertical:
160° ± 80°
Directivity Factor Rθθ
θθ
θ(Q), Median
over Indicated Range (see Figure 4),
50-125 Hz:
1.0
125-500 Hz:
5.2
Directivity Index Di(10 log Rθθ
θθ
θ),
50-125 Hz:
0.0 dB
125-500 Hz:
7.2 dB
Distortion, 0.1 Full Power Input (see
Figure 5),
Second Harmonic,
100 Hz:
0.9%
1,000 Hz:
0.9%
Third Harmonic,
100 Hz:
0.4%
1,000 Hz:
0.3%
TransducerComplement:
Two EVX-180A
Net Box Volume:
439 liters (15.5 ft3)
Box Tuning Frequency:
25 Hz
Step-Down Peak-Boost Frequency:
25 Hz
Impedance,Nominal/Minimum:
4.0/4.2 ohms
Input Connectors:
Side-mounted screw terminals (#10)
on barrier strip
Enclosure Materials and Finish:
Black texture-painted poplar plywood
Dimensions,
Height:
1210 mm (47.5 in.)
Width:
762 mm (30.0 in.)
Depth:
605 mm (23.8 in.)
Net Weight:
72.6 kg (160 lb)
Shipping Weight:
80.0 kg (176 lb)