11
10
Dolby
®
Digital, DTS
®
, DVD-Audio and Super Audio CD (SACD
™
).
Frequency responses to 50kHz, as well as three-digit dynamic
range and signal-to-noise ratio specifications have now become
commonplace. To faithfully reproduce such robust sonic properties,
the loudspeaker needed to undergo drastic improvements to its
transducer, network and enclosure technologies.
The K2 S9800 employed a three-way design, incorporating
an ultrahigh-frequency (UHF) compression driver and horn
to reproduce high frequencies up to 50kHz. With the UHF
driver handling the higher frequencies, the high-frequency (HF)
transducer could then be upgraded to a new design using a
3-inch (75mm) diaphragm, which improved reproduction of
lower frequencies and blended better with the woofer than the
older generations’ 2-inch (50mm) diaphragm did. Both of these
new compression drivers utilized newly developed beryllium
diaphragms to provide the lowest distortion and flattest frequency
response possible.
To recreate the extremely high dynamic range provided by
today’s audio sources, a brand-new low-frequency transducer
was developed from the ground up, utilizing an Alnico magnet, a
4-inch (100mm) edge-wound voice coil, and a 15-inch (380mm)
cone. Extensive computer-aided engineering and design effort
was necessary to develop the optimized port tuning employed
in Project K2 S9800, and resulted in a significant advance in the
concept of state-of-the-art acoustic reproduction. As a result of
these efforts, a loudspeaker system with higher sensitivity and a
wider dynamic range became a reality without power compression
or distortion, even at extremely high drive levels.
JBL-Ranger Paragon
JBL Everest DD55000
He went on to describe the process behind the creation of the
Hartsfield: “Most people who own and appreciate fine sound
reproduction equipment look forward to the day when they will
be able to assemble a system without limitation in just exactly
the way they think it should be done. Periodically a manufacturer
gets this same feeling. The science of acoustics has provided
us with the basic principles available to all for achieving precision
reproduction. It is only a matter of incorporating these methods into
a system design, and then taking every bit of trouble necessary to
build a system precisely to the design.”
He added, “It isn’t easy, but that’s the way it is done.”
The Ranger-Paragon, JBL’s second Project system, was the first
serious attempt at a reflecting speaker system, and broke ground
in what was at the time, the new concept of stereo imaging.
Basically two independent full-range speaker systems installed in
a handsome, curved cabinet nearly 9 feet (2.7 meters) wide, the
Paragon’s enclosure was treated as an extension of its transducers.
In essence, the system had its own “built-in acoustics.” In many
respects, the Paragon anticipated loudspeaker developments
that would occur years and even decades later. This “built-in
acoustics” concept was present in the Project Everest DD66000
and has now been further refined in the DD65000 and DD67000.
For nearly 30 years, the Paragon remained one of the world’s
most highly-regarded home loudspeaker systems. Today, along
with the Hartsfield, the Paragon is still the most sought-after
speaker in the world.
In 1986, JBL introduced a new Project system that retained the
Paragon’s overall sense of musicality while upgrading its character
by incorporating three decades’ worth of continuous development
in every facet of its design. Its name – Project Everest – reflected
the pinnacle of achievement it represented. This was the original
Project Everest DD55000.
For the first time, the rest of the sound reproduction chain – and
not the loudspeaker or its transducers – would impose limits on
overall system performance. Like the Paragon and Hartsfield,
Project Everest was built around compression driver technology
and addressed a more refined stereo image than was previously
considered technically feasible.
Since the original Project Everest was introduced, sound recording
and playback technology has undergone a revolution of its own.
With the advent of the CD, extremely demanding recorded signals
became the rule rather than the exception – the typical source
material used by the average audio enthusiast became superior
to the best demonstration material of even just a few years
prior. In overall dynamics and transient response, transducers
became once again a potentially weak link in the high-end audio
reproduction chain.
It was in this environment that JBL set out to create its fourth and
fifth Project loudspeakers, K2 S9500 and K2 S5500. As with
Hartsfield, the simplicity of a two-way system was considered the
most promising design track. Advances in transducer design and
low-frequency alignment would make possible the construction of
a two-way system of unprecedented physical and acoustical scale.
Our engineers took the core components – the low-frequency and
high-frequency transducers – and optimized them by redesigning
their magnetic structures, diaphragms and framework for greater
linearity, dynamic capability and transient response.
In the years following the introduction of the K2 S9500 and K2
S5500, sound reproduction technology underwent another series
of revolutionary changes, with the introduction of DVD-Video,
