JBL Project EVEREST DD66000, Брошюра и характеристики

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T r a n s d u c e r s
Project Everest
DD66000
Featuring a 380mm (15") pulp-cone woofer, alnico 5DG
magnet and 100mm (4") voice coil in a thick-wall cast-
aluminum frame, the 1501AL driver delivers impressively
deep, visceral bass and open, lively mid-bass sound that will
not degrade at any volume level.
Alnico was chosen because of its stable operating point. This
material is insensitive to temperature changes and back-EMF
from the coil. JBL has overcome the tendency of alnico to
demagnetize at high power levels by utilizing a massive
shorting ring at the base of the motor assembly.
The 41mm gap provides a uniform flux field for the voice
coil, causing inductance to remain essentially constant over
the entire operating range of the driver. This effectively
eliminates inductance modulation, a common source of
distortion.
The 1501AL woofer cone is a layered paper-pulp matrix
with proprietary Aquaplas damping, which delivers improved
pistonic motion across the woofer’s operating bandwidth,
and controlled cone breakup beyond it.
The outer suspension is made of EPDM foamed rubber,
which has the longevity and frequency response
characteristics of traditional rubber surrounds, but with a low
density that is very close to that of foam surrounds. Low-loss
EPDM material was chosen to preserve the crucial transient
detail of musical signals.
Dual Nomex ® spiders help to cancel out even-order
distortion. All suspension elements are tailored for maximum
mechanical displacement linearity.
The forced convection cooling of JBL’s proprietary Vented
Gap Cooling
™
technology helps lower the operating
temperature of the coil during program peaks, while
additional vents enable the pumping action of the spiders to
create even greater air circulation. This fully vented frame
and motor design also serves to minimize the back pressure
under the dome and spider, helping to reduce harmonic
distortion to even lower levels.
Taken together, the cutting-edge technologies of the
1501AL reduce harmonic distortions at both high and low
acoustic outputs, reduce power compression and deliver a
more consistent spectral balance, regardless of input levels.
Perhaps most important for people who prefer their music
at concert-level volumes, power handling is improved by as
much as 25% over earlier low-frequency drivers.
1501AL Low-Frequency Driver
1501 AL Low-Frequency Driver
Paper-pulp composite cone
Foam rubber surround
100mm Edgewound voice coil
Die-cast aluminum frame
Aquaplas damping material
Dual inverted Nomex ® spider
Alternating steel/copper gat rings
Die-cast aluminum motor housing
Polepiece
Aluminum conductive ring
Back plate
Alnico 5DG magnet