Data Sheet

ManualsBrandsEV Manuals1515" Woofer

vide a shorted turn to control inductance and

provide a major heat transfer path from the

voice coil, which improves power handling and

reduces thermal dynamic-range compression.

The voice coil itself is constructed of edge-

wound rectangular aluminum wire, mounted on

a rugged, laminated polyimide former. The com-

plete assembly is low in mass and is fabricated

using the most advanced epoxies, insulations

and materials available.

Great care was taken in the selection of dia-

phragm materials and construction to ensure

smooth, musical upper-bass reproduction and

accurate low-frequency shock capability

(punch). The cone has a moisture-repellent

treatment, allowing it to be used in harsh and

humid conditions. (Do not expose the cone to

direct water or sunlight.)

The DL15X is a true high-fidelity woofer in every

sense, being capable of high output, low distor-

tion and solid bass response.

DIRECTIONAL CHARACTERISTICS

The directional characteristics of the DL15X in

a 4.0-cubic-foot vented enclosure were mea-

sured in Electro-Voice’s large anechoic cham-

ber. The test signal was one-third-octave fil-

tered pink noise centered at the frequencies

indicated. A full spherical measurement sys-

tem, which is completely compatible with the

AcoustaCADD

computer-aided design pro-

gram, was used. All directional information was

measured at 20 feet. Figure 8 illustrates the

horizontal and vertical polar responses. Figure 6

shows the horizontal and vertical beamwidths.

Beamwidth is the angle at which the horizontal

and vertical polar responses have decreased in

level by 6 dB when compared to the axial

frequency response. Figure 7 illustrates the

total directivity of the DL15X. The directivity

factor R

(Q) is the relative value, at a point, of

the DL15X when compared to an ideal spheri-

cal response. The directivity index, D

, is calcu-

lated by the formula: D

= 10 log

TYPICAL AMPLIFIER SIZE

400-800 watts per woofer is the optimal ampli-

fier size. Amplifiers of this size will allow maxi-

mum output with minimal risk of speaker dam-

age when properly used. Smaller amplifiers

can also be used with excellent results—the full

capabilities of the speaker will simply not be

used.

POWER-HANDLING TEST

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 contin-

ued use in arduous, real-life conditions. Two

main test specifications are used: the “AES

Recommended Practice for Specification of

Loudspeaker Components Used in Professional

Audio and Sound Reinforcement” (AES2-1984/

ANSI S4.26-1984) and the “EIA Loudspeaker

Power Rating Full Range” (ANSI/EIA RS-426-A

1980). Both of these specifications use noise

spectrums which mimic typical music and test

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 com-

ponents, are also performed and passed to

ensure years of trouble-free service.

Dimensions (see Figure 10),

Outer Diameter:

384 mm (15.13 in.)

Overall Depth:

165 mm (6.48 in.)

Net Weight:

8.6 kg (19.0 lb)

Shipping Weight:

10.2 kg (22.5 lb)

DESCRIPTION

The DL15X low/mid-frequency reproducer is a

15-inch, 8-ohm driver designed for professional

high-level, high-fidelity monitoring and sound

reinforcement. At the heart of this speaker is a

carefully engineered drive system. Its design

assures linear, low-distortion output, high power

capability and efficient heat transfer.

Incorporated into the design are three exclu-

sive Electro-Voice innovations. PROTEF

coat-

ing (U.S. patent #4,547,632), a Teflon

-based

coating, is applied to the inside diameter of the

top plate.

Occasional violent power peaks of

several seconds may expand a transducer’s

voice coil into contact with the top plate, caus-

ing failure. PROTEF provides protection against

such failure. The coating lubricates any rubbing

contact and provides electrical insulation be-

tween the coil and the steel top plate. The

Thermo Inductive Ring (TIR

) and Flux De-

modulation Device (FDD

), also included in

the DL15X design, are aluminum castings

fastened to the pole of the magnet. They pro-

Specifically, the DL15X passes ANSI/EIA

RS-426-A 1980 with the following values:

= 6.9 ohms (1.15 x R

)

(max) = 400 watts

Test voltage = 52.5 volts rms,

105.0 volts peak

(+6 dB)

The DL15X passes AES2-1984/ANSI S4.26-

1984 with the following values:

MIN

= 8.0 ohms at 230 Hz

(max) = 400 watts

Test voltage = 56.6 volts rms,

113.2 volts peak

(+6 dB)

Selected decade = 50-500 Hz

RESPONSE IN STANDARD BAFFLE

AES requires a large, planar baffle for this test,

WHICH IS INTENDED TO SHOW SMOOTH-

NESS AND OFF-AXIS RESPONSE, NOT

BASS RESPONSE. This has proven to be

inconvenient and prohibitive, due to its size.

Here, we have chosen our lab-standard, low-

diffraction, 12-cubic-foot test enclosure, which

will demonstrate the same characteristics as

the AES standard baffle (see Figure 2). A

smoothed swept-sine-wave input is used for

this measurement to provide a more informa-

tive curve to the end user.

TYPICAL ENCLOSURES

The most extended bass, lowest distortion and

best control is usually realized in properly de-

signed vented enclosures. In such designs, the

vent, or port, actually provides the lowest oc-

tave 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 enclosure. The excursion of the DL15X

at these frequencies is much reduced com-

pared to sealed or open-back enclosures, di-

rectly reducing harmonic distortion and the

possibility of speaker bottoming. See Figure

11 for maximum potential output over the fre-

quency range. Vented-enclosure recommen-

dations follow, some incorporating low-fre-

quency equalization. Thiele-Small parameters

are provided so designers can tailor the re-

sponse to suit their needs.

Normally Tuned Enclosures

See Figures 9A and 9B. The 6-cubic-foot

enclosure is tuned to 35 Hz and has an ex-

tended response to below 40 Hz. The 4-foot

enclosure has a response that "bumps up” from

60 to 110 Hz but has less extended low-bass

output.

Also, Pro Sound Facts No. 7, “DL Series Woof-

ers—Plans for Recommended Vented Enclo-

sures and Small- and Large-Signal Performance

for These Enclosures,” is available from Electro-

Voice at no charge. A wide variety of enclosure

sizes and degree of low-frequency extension is

described in this literature.

Step-Down Operation

The “step-down” mode approximates a B

Thiele

alignment. Step-down extends system low-fre-

quency response by increasing amplifier power

at certain frequencies instead of enclosure

size. In step-down, the enclosure is tuned to a

lower frequency than normal. This increases

system output in the region of the new tuning

frequency and reduces output slightly in the

region of original tuning. The smoothly falling

response which results can be equalized to

_______________________

4. Teflon

is a registered trademark of DuPont.

FIGURE 10A — Predicted Low-Frequency

Response in a Typical

Enclosure (4.0 ft

tuned to 35 Hz)

FIGURE 10B — Predicted Low-Frequency

Response in a Typical

Enclosure (6.0 ft

tuned to 30 Hz)

FIGURE 11 — Maximum SPL at 1 Meter in

Typical Enclosure

(4.0 ft

tuned to 35 Hz)