Electro-Voice TL606DMT User manual

TL606DMT
Low-Frequency Speaker
System
• High efficiency and low distortion
• 2 DL15MT woofers for increased
longevity under extreme power
conditions
• Versatile system design
capabilities
Description
The Electro-Voice TL606DMT is an opti-
mally vented, direct-radiator speaker system
for high-output reproduction of low fre-
quency to 40 Hz. The TL606DMT's design
based on the vented-enclosure modeling
technique of A.N. Thiele and R.H. Small,
which makes possible a combination of high
efficiency, low-distortion and extended low-
frequency performance in an enclosure of
moderate size.
The TL606DMT employs dual DL15MT
very-low-frequency reproducers in a 9-cu-
bic-foot (255 liter) enclosure. The
DL15MT's high linear cone-excursion abil-
ity (Xmax=0.22 inches, zero to peak) and
400-watt long-term average power capacity
contribute substantially to the TL606DMT's
high acoustic output ability (see Power
Handling Capacity section).
Applications
The TL606DMT was specifically designed
for use with the Variplex cinema three-way.
It's high excursion, low distortion and lon-
gevityunderextremepowerconditionsmake
it an intricate component for producing the
dynamic clarity of the Variplex System. The
TL606DMT is also deally configured for a
wide variety of high-output, low-frequency
reinforcement applications in permanently
installed sound systems. Typical venues in-
clude cinemas, auditoriums, theaters, per-
forming arts centers, night clubs and con-
cert halls. The TL606DMT is designed to
serve as the primary low-frequency section
in extended-response two-way systems with
excellent bass performance to 40 Hz and
controlled dispersion to 800 Hz—a typical
crossover frequency of two-way systems.
When used with the dedicated XEQ-504
crossover/equalizer, the TL606DMT can be
combined with appropriate Electro-Voice
TransPlanarTM horns and DH series drivers
to form a passive two-way system of
unprecedented wide-range response and lin-
earity. However, to extract the maximum
performance from the TL606DMT, a
multiamp configuration using the XEQ-2 or
XEQ-3 crossover/equalizer units is recom-
mended so that full rated power may be ap-
plied to the low-frequency system. With a
half-power point of 40 Hz, the TL606DMT
can also serve as the subwoofer component
in large, multiway systems.
Frequency Response
The TL606DMT frequency response was
measured in an anechoic environment at 10
feetonaxis with swept one-third-octave pink
noise. The frequency response curve for the
TL606DMT are shown in Figure 1.
Directivity
The TL606DMT directional characteristics
were measured by running a set of polar-re-
sponse curves in EV’s large, anechoic cham-
ber. The test signal was one-third-octave
pseudo-random pink noise centered at the
frequenciesindicatedin Figure 2. The curves
show horizontal (side-to-side) dispersion
when the enclosure’s long axis is vertical.
The vertical (up-and-down) polar responses
are also shown.
Additional typical information is provided
in Figure 3 which shows 6-dB-down
beamwidthversusfrequency. Figure 4 shows
the directivity factor and directivity index
versus frequency.
Distortion
FollowingAES(AudioEngineeringSociety)
recommended practice, plots of second- and
third-order harmonic distortion for 0.1 rated
input power are shown in Figure 5.

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
2
Power Handling Capacity
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 signalbecause 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
testsignalincludesnotonlytheoverall“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 actual pro-
gram. The long-term average level stresses
the speaker thermally (heat). The instanta-
neouspeaks test mechanical reliability (cone
and diaphragm 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 sec-
onds on up, but we apply the long-term av-
erage for several hours, adding another ex-
tra measure of reliability.
Specifically, the TL606DMT is designed to
withstand the power test described in EIA
Standard RS-426A. The EIA test spectrum
isapplied for eight hours. Toobtain thespec-
trum, the output of a white noise generator
(white noise is a particular type of random
noisewithequal energy per bandwidth in Hz)
is fed to a shaping filter with 6-dB-per-oc-
tave slopes below 40 Hz and above 318 Hz.
When measured with the usual constant-per-
centage analyzer (one-third-octave), this
shaping filter produces a spectrum whose
3-dB-down points are at 100 Hz and
1,200Hzwith a 3-dB-per-octave slope above
1,200 Hz. This shaped signal is sent to the
power amplifier with the continuous power
set at 800 watts into the 3.5 ohms EIA
equivalent impedance for the TL606DMT
(52.9 volts true rms).
Amplifier clipping sets instantaneous peaks
at 6 dB above the continuous power, or
3,200 watts peak (105 volts peak). This
procedure provides a rigorous test of both
thermal and mechanical failure modes.
SubpassbandSpeaker Protection
Below the enclosure tuning frequency, cone
excursion increases rapidly. Since acoustic
output is also failing rapidly, there is no util-
ity in driving the system with signals much
below the tuning frequency. While such sig-
nals may be in the program material, they
are often extraneous—such as from record-
surface irregularities (strong 5- to 25-Hz
components) or a dropped microphone. The
DL15MT very-low-frequency reproducer is
ruggedly designed and has a high maximum
excursion before damage (±0.5 inch). How-
ever,high-output subwoofersystems such as
the TL606DMT should be protected by a
high-passfilter with a 3-dB-down corner fre-
quency of about 0.8 the enclosure tuning fre-
quency. Below the corner frequency, a roll-
off of 12-dB-per-octave is usually sufficient.
Withoutprotection, subpassband signals may
“bottom”theDL15MT’s.Damagewillprob-
ably result, especially after repeated occur-
rences. Even if bottoming does not occur,
the subpassband signals waste amplifier
power and modulate (distort) the frequen-
cies which are within the TL606DMT’s op-
erating range. Much “woofer distortion” or
“muddy bass” can be attributed to lack of
subpassband protection.
The Electro-Voice EX-24, XEQ-2 and
XEQ-3 electronic crossover/equalizers pro-
vide subpassband protection. The 3-dB-
down points are 30 Hz (EX-24 and XEQ-2)
and 16 Hz or 32 Hz (XEQ-3).
Other high-pass filters are available, and
one-third-octave equalizers can also be ef-
fective at providing the required protection.
Use in Multiples
TL606DMT’s may be used in multiples to
increaseacoustic output. In the following dis-
cussion, it is assumed that all speaker cones
are operating in unison (in phase) when a
common signal is applied. A 6-dB increase
in maximum acoustic output results when
two speakers are located side by side. For
operationatverylowfrequencies,thewoofer
cones “mutually couple,” acting as one
speaker with cone area and power-handling
capacity twice that of a single speaker. The
doubling of cone area doubles efficiency,
providing a 3-dB increase in sound pressure
level. The second 3 dB comes from the dou-
bling of power capacity.
Mutual coupling occurs when the frequency
is such that the center-to-center distance be-
tween the two speaker cones is less than
about one-quarter wavelength. For a given
center-to-center distance, the highest fre-
quency at which mutual coupling will occur
can be calculated from the following for-
mula:
3,000
f = —————,
Dmax
where Dmax is the distance in inches and f is
frequency in Hz. When Dmax is greater than
one-quarter wavelength, as would occur if
two TL606DMT’s were widely spaced, the
level increase tends to be limited to the
3-dB power-handling increase.
More than two TL606DMT’s can be used
for increased output. In general, maximum
acousticpoweroutput ability increases as the
square of the number of mutually coupled
cones. For example, four cones would pro-
vide 42or 16 times the power output of a
single cone, an increase of 12 dB (10 log10
16 = 12 dB). Note that the associated in-
creased efficiency (2.9% X 4 = 12%) ap-
proaches that of a fully horn-loaded design,
but in a much smaller enclosure.
System Positioning
Subwoofer systems such as the TL606DMT
are often located on the floor. This is both
convenient and can provide a desired high
acoustic impact when the speakers are, for
example,placed near the periphery of a dance
floor. In other installations, such as a theater
or auditorium, the audible location of a sub-
woofer operating at a sufficiently low cross-
over frequency (below about 125 Hz) will
not be particularly evident. The other sys-
temelements operating above the subwoofer
range can be positioned for the desired
locational cues and uniform audience cov-
erage.
Floor location provides the acoustic half-
space environment associated with the 5.8%
systemefficiencynoted in theSpecifications
section. Location at a floor-wall junction
(acoustic quarter space) doubles efficiency

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
3
certified suspension kit shall be available to
suspendtheTL606DMT horizontally (model
HS6) or vertically (model HS7). Internal
1/4-20 threaded fasteners provide a method
of mounting high-frequency or mid-high
devices to the system. The system shall be
the Electro-Voice TL606DMT.
Warranty (Limited)
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 theindividual 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 theindividual 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
Electro-Voiceor any ofitsauthorized service
representatives. Obtaining Warranty Ser-
vice:To obtain warranty service, a customer
must deliver the product, prepaid, to
Electro-Voice Serviceor any of its authorized
service representatives together with proof
of purchase of the product in the form of a
bill of sale or receipted invoice. A list of au-
thorized service representatives is available
from Electro-Voice Service at 600 Cecil
Street, Buchanan, MI 49107 (800/234-6831
or FAX [phone]). 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
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
given to the instructions and limitations in
the HS kit instruction sheet.
Accessories for Special Systems
The TL606DMT was designed to be used
withElectro-Voice TransPlanarTM horns, DH
series compression drivers and accessories
to form passive, 500 Hz crossover systems
that may be easily and quickly assembled
and installed. A 500-Hz passive crossover,
the XEQ-504, directly replaces the
TL606DMT’sinput panel.Mountingkits,the
HMK-1 and HMK-2, provide the necessary
hardware and accessories to mount the
HP940/DH1A and HP9040/DH1A horn/
driver combinations, respectively, to the
TL606DMT box. Steel threaded inserts are
provided on the top panel of the box to
accommodate mounting kits for both horn
combinations.
Architects’ and Engineers’
Specifications
The loudspeaker system shall consist of two
380-mm (15-in.) very-low-frequency repro-
ducers installed in a vented enclosure. The
frame of the reproducer shall be manufac-
tured of cast aluminum, and its magnetic as-
semblyshall utilize a ferrite magnet. An alu-
minum ring mounted to the top of the pole
piece shall act as a control on drive induc-
tance and provide a heat-transfer path from
the top of the voice coil. The inner surface
of the top plate shall be coated with
PROTEFTM,a Teflon®-basedcoating used for
prevention of damage to the voice coil.1
Performance specifications of a typical pro-
duction unit shall be as follows: measured
sensitivity (SPL at 1 m on axis with 1 W
input, swept 100-800 Hz) shall be at least
100 dB SPL; usable frequency range shall
extend from 30 Hz to 3,500 Hz; nominal
impedanceshallbe 4 ohms; rated power han-
dling capacity shall be at least 800 watts,
conforming to EIA standard RS-426A.
The enclosure shall be solidly constructed
of19-mm(3/4-in.) stock with all joints tightly
fitted and glued. Overall dimensions shall
be no greater than 100.3 cm (39.5 in.) high
by 57.2 cm (22.5 in.) wide by 44.7 cm
(17.6 in.) deep. Finish shall be black vinyl
with leatherette pattern. An independently
(a3-dB increase in sound pressure level) and
tends to promote the full excitation of more
room modes, or standing waves, important
in achieving maximum overall bass output
in the room. Corner placement (acoustic
eighth space) doubles efficiency again and
guarantees excitation of all room modes.
(Such placement for maximum efficiency
and room-mode excitation is not necessary
and may not be desirable or possible for a
variety of reasons, including aesthetics and
building design.)
The TL606DMT can also be successfully
operated away from any nearby acoustic
boundaries, particularly when multiple
systems are used for increased output ability
(see Use in Multiples section).
Suspending TL606DMT Enclosures
The TL606DMT is designed for typical cin-
ema stage (behind-the-screen) applications
where low-frequency systems are mounted
on platforms, behind the screen and some
distance above the stage floor. The
TL606DMTis not designed to beself-sus-
pended, and if suspended, must be sup-
ported and hung in a way which does not
depand on the structure of the TL606DW
itself for support.
TheHS6andHS7kitsallow the TL606DMT
to be hung safely in a variety of orientations.
The combination of the correct HS kits and
TL606DMT enclosure has been certified by
an independent structural engineer to be safe
and secure. Each HS kit consists of a steel
tube,two brackets, two eyebolts and the nec-
essaryfasteners. The installer must assemble
the HS kit by first drilling two holes into the
TL606DMT enclosure, in predefined posi-
tions, and then screwing the brackets onto
the steel tube, which passes through the en-
closure. An eyebolt is inserted in the T-nut
in the rear panel of the enclosure to provide
a“pull up” to aim the enclosure. Fullinstruc-
tions and hole locations are included with
each cabinet and HS kit. A TL606DMT re-
quires a single HS6 to suspend it horizon-
tally, or a single HS7 to suspend it vertically.
Electro-Voice recommends that only one
TL606DMTbe suspended at one time in
this manner. Vertical is defined as having the
long side vertical. Full attention must be

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
4
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-
temsare guaranteed againstmalfunction due
to defects in materials or workmanship for a
periodoffive(5)yearsfrom the date of origi-
nalpurchase.The Limited Warranty 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.
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.

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
5
100 Hz 160 Hz
200 Hz 250 Hz 315 Hz
400 Hz 500 Hz
50 Hz 60 Hz 80 Hz
Figure 1—Polars HORIZONTAL
VERTICAL
5 dB per division
125 Hz

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
6
Figure 3—Beamwidth
Figure 4—Directivity
FREQUENCY
LEVEL IN (dB)
DIRECTIVITY
INDEX Di(dB)
HORIZONTAL
VERTICAL +
Figure 2—Frequency Response
4 volts/10 feet

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
7
Figure 6—Vertical & Horizontal
Mounting Methods for the TL606DMT
Using the BMK-1 Hanging Kit
Figure 5—Harmonic Distortion
0.10 rate powwer input (80 watts)
10 feet on axis
FREQUENCY
LEVEL IN (dB)

TL606DMT Low-Frequency Speaker System
TL606DMT Low-Frequency Speaker System
8
specifications
Frequency Response, 10 Feet on Axis,
Swept One-Third-Octave Pink Noise,
Half-Space Anechoic Environment
(see Figure 1):
40-3,500 Hz
Low-Frequency 3-dB-Down Point,
Normal:
40 Hz
Usable Low-Frequency Limit (10-dB-
down point), Normal:
30 Hz
Half-Space Reference Efficiency:
5.8%
Long-Term Average Power Handling
Capacity per EIA Standard RS-426A
(see Power Handling Capacity section):
800 watts
Maximum Long-Term Average Mid-
Baud Acoustic Output:
11.6 watts
Sound Pressure Level at 1 Meter, 1
Watt Input, Anechoic Environment,
Band-Limited Pink-Noise Signal,
100-800 Hz:
100 dB
40-125 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),
40-125 Hz Horizontal and Vertical:
360°
400-800 Hz Horizontal:
120° ±12°
400-800 Hz Vertical:
55° ±14°
Directivity Factor Rq(Q), Median Over
Indicated Range (see Figure 4),
40-125 Hz:
1.8
400-800 Hz:
5.7
Directivity Index Di, Median Over
Indicated Range (see Figure 4),
40-125 Hz:
0.0 dB
400-800 Hz:
7.6 dB
Distortion, 0.1 Full Power Input (see
Figure 5),
Second Harmonic,
100 Hz:
0.45%
500 Hz:
0.28%
Third Harmonic,
100 Hz:
0.14%
500 Hz:
0.89%
Transducer Complement:
Two DL15MT woofers
Box Tuning Frequency:
40 Hz
Impedance, Minimum:
4 ohms
Input Connections:
Screw terminals (#8-32) on barrier strip
Enclosure Materials and Finish:
Black, vinyl-clad particle board
Suspension (see Suspending TL606DW
Enclosures section):
Two “independently certified” suspen-
sion kits are available, the HS6 and HS7
Dimensions,
Height:
100.3 cm (39.5 in.)
Width:
57.2 cm (22.5 in.)
Depth:
44.7 cm (17.6 in.)
Net Weight:
49.0 kg (108 lb)
Shipping Weight:
54.4 kg (120 lb)
SPEAKERS-Low-Frequency Part Number 534628 — 9833
600 Cecil Street, Buchanan, MI 49107
800/234-6831, 616/695-6831, 616/695-1304 Fax, www.electrovoice.com
©Telex Communications, Inc. 1998 • Litho in U.S.A.