Inlroduclion - JBL D208H Instruction Manual

Excellence is an elusive quality It's so easy to recognize yet so difficult
to attain
JBL craftsmen have been involved in the art of sound (or more than
a generation signal and source, wood and fabric, transducers and
acoustics—all of it
Today these craftsmen continue to perform to the most rigid standards
any craftsman can submit to: those they impose upon themselves.
JBL loudspeakers are carefully engineered instruments, painstakingly
crafted and assembled to watchmakers' standards. JBL enclosures
express the excitement of creative design; they are elegant, solid and
flawlessly finished. JBL transducers and electronics offer what has been
characterized by devoted music listeners as the incomparable JBL sound.'
By following the few simple suggestions contained in this booklet,
you can look forward to superb high fidelity reproduction that will retain
its clarity and realism year after year.
Every JBL loudspeaker system is the product of extensive listening
evaluation combined v/ith exhaustive research and testing, using the most
sophisticated equipment and methods available. JBL system recommen-
dations are based on subjective evaluation of component performance
as well as efficiency and eleclrical characteristics These and other critical
factors must be integrated by a frequency dividing network engineered
for the specific components of the system
A well-built, sturdy enclosure is essential for optimum bass performance.
An enclosure having the proper internal volume and tuning for the loud-
speaker increases low frequency dynamic range and improves tonal
quality: it also reduces distortion and the possibility ol overdriving the
loudspeaker.
Detailed guidance on enclosure construction may be obtained from
your JBL Loudspeaker Components dealer who may also supply the
JBL Enclosure Construction Kit. An illustrated brochure with a discussion
of loudspeaker theory as woll as detailed enclosure construction tuning
and finishing instructions for home entertainment and musical instrument
applications is contained in the kit Actual construction drawings and
"Loudspeaker Components by JBL' nameplates for your finished
enclosures are also included.
JBL transducers are precision instruments responding with high accuracy
to the variations in electrical current produced by other components in
the music system Extraneous noises, such as hum. rumble, crackling
or hissing do not originate in the loudspeakers If you experience difficulty
realizing the fine performance built into your JBL components, consult
the JBL Loudspeaker Components dealer from whom they were
purchased. He is equipped with the knowledge required to provide expert
advice and assistance. If. for some reason, your JBL dealer is unable to
assist you, or you cannot find the answer you need published in JBL
literature, write directly to the JBL Technical Services Department describ-
ing the difficulty in detail: please be certain that your return address and
telephone number are clearly printed on your correspondence.
Introduction
1