Electro-Voice dl15st eds ユーザーズマニュアル
DL15ST
Low-Frequency
Reproducer
General Product Description
The DL15ST 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.
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 exclusive Electro-Voice®
innovations. PROTEF
innovations. PROTEF
™
coating (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, causing failure.
PROTEF™ provides protection against such failure. The coating
lubricates any rubbing contact and provides electrical insulation between
the coil and the steel top plate. The Thermo Inductive Ring (TIR
Occasional violent power peaks of several seconds may expand a
transducer’s voice coil into contact with the top plate, causing failure.
PROTEF™ provides protection against such failure. The coating
lubricates any rubbing contact and provides electrical insulation between
the coil and the steel top plate. The Thermo Inductive Ring (TIR
™
) and
Flux Demodulation Device (FDD
™
), also included in the DL15ST design,
are aluminum castings fastened to the pole of the magnet. They provide
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.
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 complete
assembly is low in mass and is fabricated using the most advanced
epoxies, insulations and materials available.
wire, mounted on a rugged, laminated polyimide former. The complete
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 diaphragm 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.)
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 DL15ST is a true high-fidelity woofer in every sense, being capable
of high output, low distortion and solid bass response.
of high output, low distortion and solid bass response.
Architects’ and Engineers’ Specifications
The low frequency woofer shall have a nominal diameter of 350 mm
(15 in.), an overall depth of 165 mm (6.48 in.) and weigh less than 8.6
kg (19.6 lb). The frame shall be constructed of strong,
deformation-resistant die-cast aluminum. The magnet assembly shall
incorporate PROTEF™ protection, a TIR™ (Thermo Inductive Ring)
and FDD™ (Flux Demodulation Device) to reduce inductive coupling
and increase power handling. The cone and dust dome should withstand
use in damp and humid conditions. The voice coil shall have a diameter
of 63.5 mm (2.5 in.), a winding depth of 15.2 mm (0.6 in.) and be made
of edge-wound aluminum ribbon. The voice-coil former shall be made
of aerospace-grade polyimide laminate and bonded with
high-temperature epoxy adhesives. The performance specification of a
representative production 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 in excess of 98 dB. The reference efficiency shall be at least 4.63%.
The usable response shall be 45 to 3,000 Hz, and the nominal
impedance shall be 8 ohms. The EIA rated power shall be 400 watts.
The low-frequency transducer shall be the Electro-Voice® DL15ST.
(15 in.), an overall depth of 165 mm (6.48 in.) and weigh less than 8.6
kg (19.6 lb). The frame shall be constructed of strong,
deformation-resistant die-cast aluminum. The magnet assembly shall
incorporate PROTEF™ protection, a TIR™ (Thermo Inductive Ring)
and FDD™ (Flux Demodulation Device) to reduce inductive coupling
and increase power handling. The cone and dust dome should withstand
use in damp and humid conditions. The voice coil shall have a diameter
of 63.5 mm (2.5 in.), a winding depth of 15.2 mm (0.6 in.) and be made
of edge-wound aluminum ribbon. The voice-coil former shall be made
of aerospace-grade polyimide laminate and bonded with
high-temperature epoxy adhesives. The performance specification of a
representative production 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 in excess of 98 dB. The reference efficiency shall be at least 4.63%.
The usable response shall be 45 to 3,000 Hz, and the nominal
impedance shall be 8 ohms. The EIA rated power shall be 400 watts.
The low-frequency transducer shall be the Electro-Voice® DL15ST.
Directional Characteristics
The directional characteristics of the DL15ST in a 1.1-cubic-foot vented
enclosure were measured in Electro-Voice’s large anechoic chamber.
The test signal was one-third-octave filtered pink noise centered at the
frequencies indicated. All directional information was measured at 20
feet. Figure 1 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 2 illustrates the total directivity of the DL15ST. The
directivity factor R
enclosure were measured in Electro-Voice’s large anechoic chamber.
The test signal was one-third-octave filtered pink noise centered at the
frequencies indicated. All directional information was measured at 20
feet. Figure 1 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 2 illustrates the total directivity of the DL15ST. The
directivity factor R
θ
(Q) is the relative value, at a point, of the DL15ST
when compared to an ideal spherical response. The directivity index,
D
D
i
, is calculated by the formula: D
i
= 10 log
10
R
θ
.
Electrical Connections
The DL15ST is fitted with a pair of plated, frame mounted connectors
with color-coded ends. Electrical connection is made by pushing down,
inserting wire completely through the rectangular slot and releasing
pressure. One conductor of #9 stranded, #8 AWG solid, a pair of twisted
#15 AWG stranded or a pair of #14 AWG solid conductors will fit.
with color-coded ends. Electrical connection is made by pushing down,
inserting wire completely through the rectangular slot and releasing
pressure. One conductor of #9 stranded, #8 AWG solid, a pair of twisted
#15 AWG stranded or a pair of #14 AWG solid conductors will fit.
Typical Amplifier Size
400-800 watts per woofer is the optimal amplifier size. Amplifiers of this
size will allow maximum output with minimal risk of speaker damage
when properly used. Smaller amplifiers can also be used with excellent
results.
size will allow maximum output with minimal risk of speaker damage
when properly used. Smaller amplifiers can also be used with excellent
results.
Typical Enclosures
The most extended bass, lowest distortion and best control is usually
realized in properly designed vented enclosures. In such designs, 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 enclosure. The
excursion of the DL15ST at these frequencies is much reduced
compared to sealed or open-back enclosures, directly reducing harmonic
distortion and the possibility of speaker bottoming. Thiele-Small
parameters are provided so designers can tailor the response to suit
their needs.
realized in properly designed vented enclosures. In such designs, 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 enclosure. The
excursion of the DL15ST at these frequencies is much reduced
compared to sealed or open-back enclosures, directly reducing harmonic
distortion and the possibility of speaker bottoming. Thiele-Small
parameters are provided so designers can tailor the response to suit
their needs.
Normally Tuned Enclosures
A 1.8 cubic-foot enclosure tuned to 55 Hz has a smooth extended
response to below 50 Hz. The 1.1 cubic-foot enclosure “bumps up”
above 70 Hz but has less extended low-bass output.umps up” above
70 Hz but has less extended low-bass output.
response to below 50 Hz. The 1.1 cubic-foot enclosure “bumps up”
above 70 Hz but has less extended low-bass output.umps up” above
70 Hz but has less extended low-bass output.
Figure 1