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Mid-Frequency TransducerFigure 2 Century 500
Mid-Frequency Transducer
The Century Gold also features an all-new 5" (127mm) mid-frequencyRubber/vinyl 0.4" (11mm) long, 2" (50mm)
surrounddiameter edgewound
transducer developed speciŢcally for the Century Gold (Figure 2). Thealuminum voice coil for
high linearity and
voice coil is 2" (50mm) in diameter and wound on edge from �at aluminumpower handling
a
ribbon wire to a depth of precisely .4" (11mm) on a thermoset composite
Kevlar
¨
form. The cone is made of Kevlarwith a composite rubber/vinyl surround.coneVented pole piece allows
driver to run cooler
Kevlar was chosen for the cone material because it is extremely strong and
rigid while relatively low in mass. This allows the driver to move fast
enough to reproduce the dynamics of the critical midrange frequencies while
Neodymium magnet provides
high flux density with low mass
retaining the low distortion characteristics necessary for accurate musical
Diecast aluminum frame
reproduction. Its very high power capability and freedom from breakupfor high strength
make it an ideal midrange in a system that is designed to play at high levels
with absolutely no signs of distress. It makes the transition from the woofer
at 600Hz, providing good dispersion throughout the important vocal range.
High-Frequency Transducer
No.
Throughout the history of high-frequency transducer design, the goal of
extended frequency response has been at odds with the need for high
4
power handling. JBL has long chosen titanium as the material for its
highest quality high-frequency transducers and theCentury Gold is
no exception (Figure 3). Titanium possesses the essential requirements forFigure 3 050 Gold
High-Frequency Transducer
a high-frequency transducer. First, titanium is extremely light yet rigid.
The goal is to maintain a piston-like action as high in frequency as possible.
Titanium dome
If the material �exes easily, the diaphragm will break up into random
vibrations. Second, titanium is virtually free from fatigue. The material
is virtually immune from the cumulative effects of millions of �exures
1" copper
Cast zinc faceplate
over long operating periods. These factors, coupled with the higher powervoice coil
for less resonanceprovides
smooth
handling that titanium affords, allow us to produce an extremely smoothperformance
and high
high-frequency transducer with extended frequency response that can handlepower
handling
all the demands of todayOs digital programs. |
ACEC
HARMAN KARDON
