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The Project Everest was a loudspeaker designed to inherit
the legacy of the great speakers from JBL. In this respect, it was a
remarkable success. It was a visual and sonic statement that defined the art
of JBL in the 1980's. It was described as JBL's third "Project" speaker,
with the first and second being the Hartsfield and Paragon. These project
speakers were meant to be the "absolute peak of every technological,
material and engineering innovation available to the art and science of
audio at that time."
The Everest was the brainchild of Bruce Scrogin, the then
President of JBL International. Bruce recognized that there remained demand
for a "statement" speaker after the Paragon ended production in 1983. This
demand was almost exclusively from Japan, so it was decided that a follow-on
to the Paragon should be targeted at that market. Development was undertaken
from a team approach with Bruce providing the concept and leadership, Greg
Timbers the engineering, and Dan Ashcraft the industrial design. To provide
input on the unique requirements of the Japanese market, Keizo Yamanaka, a
preeminent Japanese audio reviewer, was hired by JBL on retainer to consult
on both acoustic and visual issues.

"Defined Directivity"
© Harman International
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The design went through a fairly extensive evolution
before arriving at the final configuration. Originally, the concept was to
develop a "super L300" with a similar sonic character. It was given the working
designation of the L400. However, that designation had a notorious past and
was soon dropped (see sidebar below). The system would be designed around a
new acoustic concept referred to as "Defined Directivity" (the DD in
DD55000). This concept had been pioneered by Don Keele in the professional
4660 ceiling speaker. That speaker was intended to provide rectangular
coverage with constant volume from front to back. Bruce Scrogin realized
that mounting this horn sideways in a home system could provide constant
horizontal coverage. The asymmetric design would force more sound to the
distant axis compared to the near axis so that someone walking a horizontal
line between the speakers would be exposed to a constant sound level.

Everest Prototype
© Audio & Video Life Magazine (Japan),
Courtesy Greg Timbers
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The first prototype was developed in 1984 and consisted a
four-way configuration. The Japanese press toured Northridge at that time
and sketched this original prototype. It was later included in a cartoon on
the development of the Everest. It is the only illustration that remains of
this system. Numerous problems existed in this prototype related to the
integration of the four drivers. It was decided to simplify the design to
result in what was fundamentally a two-way concept. A super tweeter would
later be added to provide extension to the highest octaves. Therefore, the
final configuration became a three-way system.

L400
© Harman International, Courtesy Greg
Timbers
Above is an excerpt from
JBL's 1975 catalog illustrating a "mystery speaker" referred to as the
L400. The only description says, "Coming soon. The L400, with the
promise that it will be the most exciting fusion of art and technology
yet presented by JBL." It never came.
Originally, the speaker was planned to be a domestic conversion of the
4340 monitor, similar to the L300 conversion of the 4333 monitor. It
would be a four-way speaker using a 15" low frequency driver, 10"
midbass, 1" throat compression driver midrange and slot tweeter. The
main development work in converting this speaker for domestic use
centered on network design changes, a revised midrange horn and
aesthetics suitable for a home environment
There were three separate attempts to bring this speaker to market. All
failed before a final decision was made to cancel the project. The
primary difficulty was developing a system that could be sold at a
reasonable cost. However, there were also technical issues and no one
was satisfied with the ultimate sound of the prototypes.
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The bass driver selected for the Everest was the
professional E145. It was chosen because it was the "fastest" bass driver in
JBL's inventory. While initially intended as a guitar speaker, its
remarkably flat given an underhung voice coil topology and maintains
pistonic action throughout its range due to a deep, straight-sided cone. The
magnetic motor is oversized compared to other JBL 15" drivers and was based
on LE15H. It resulted in a very efficient bass response that would match the
target system sensitivity of 100db/w/m. The deep cone was accommodated by an
extension ring added to the rim of the speaker basket that was very similar
to the 150-4C of the 1950's. Therefore, it was not a complete stretch to
label it a 150-4H as was done in the Everest product literature.
Normally, the bass extension of the E145 is considered
somewhat limited, but given a large enough box, it could provide real, deep
bass. This was the reason for the huge enclosure. The bass section was
designed for an internal volume of 8 cu ft. Initially, it was planned that
the volume behind the midrange horn could be used as part of the bass
enclosure. However, the fiberglass horn was not sufficiently rigid to
prevent resonances from the back pressure. Ultimately, this part of the
enclosure was partitioned off and compounded the need for a huge cabinet.

Everest Driver
Configuration
© Harman International, Courtesy
Greg Timbers
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The Everest used a one inch throat compression driver
(pro model number 2425) attached to the previously mentioned asymmetric horn
(model number 2346) for the midrange. A one inch driver was selected since
the original 4660 horn was designed around such a driver. A two inch driver
could have provided superior response, but the larger throat would have
presented problems in pattern control. A 2405 slot tweeter was added for
extreme high frequency response.
The overall system was designed for a specific sonic
character that appealed to the Japanese market. In general, it is marked by
an overdamped bass response with the lowest octave gently rolled off. The
bass is expected to extend to the deepest octave but not at the same volume
level as the upper bass. This is not meant to be a euphonic characteristic,
but rather a reflection of typical Japanese listening rooms. Their smaller
rooms, compared to North America, tend to equalize the in-room response to
result in a bass response that is relatively flat.
The industrial design was primarily the responsibility of
Dan Ashcraft of Ashcraft Designs, with input from Bruce Scrogin and Keizo
Yamanaka. This was Dan's first commission from JBL. It was somewhat of a
trial by fire at which he succeeded admirably. It was a very complicated
design since a goal was to make this massive system visually less imposing.
The inventive use of angled faces deliberately concealed the depth of this
system. .The woofer was angled a bit to "cheat" the low frequency
directionality and the super tweeter was purposely angled to aim at the
center listening position due to its directionality.
The Everest was an immediate success. It was named
"Product of the Year" in 1985 by Japan's Stereo Sound magazine. There was no
predetermined production run, but it is thought that around 500 pairs were
produced. It continued in regular production until the introduction of the
K2 in 1989. However, it was still possible to special order the Everest for
the next couple of years. They were never marketed outside of the
International Division and were almost exclusively sold in Japan. However,
some made it into Canada and Europe as they were territories within the
International Division.
© 2001 Don McRitchie
based on information provided
by Greg Timbers
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