JBL CS12 User Manual
Page 2
INSTALLATION WARNINGS
AND TIPS
CHOOSING AN ENCLOSURE
ABOUT THESE
INSTRUCTIONS
Subwoofer installation often
requires woodworking skills and
some experience disassembling
and reassembling automotive
interiors.
If you lack the tools or necessary
skills, have your subwoofer
installed by an authorized JBL
dealer.
In order that we may better serve
you should you require warranty
service, please note your serial
number, and retain your original
sales receipt
WARNING! LOUD
MUSIC AND HEARING
Playing loud music in an auto-
mobile can permanently damage
your hearing as well as hinder your
ability to hear traffic. We recom-
mend listening at low levels while
driving. JBL accepts no liability for
hearing loss, bodily injury or
property damage resulting from use
or misuse of this product.
CS subwoofers are optimized
to perform best in small, sealed,
vented and prefabricated bandpass
enclosures. While infinite-baffle
mounting of CS subs is possible,
power handling will be greatly
compromised because there’s no
enclosed volume of air to prevent
the speaker’s cone from moving
past its limit. For this reason, we
do not recommend infinite-baffle
mounting for CS subwoofers.
You should choose the enclosure
you will use based on the type of
music you listen to, how much
amplifier power you will use for the
subwoofer and how much space
inside the vehicle you can devote
to a subwoofer enclosure.
Because a sealed enclosure
provides the most control over the
woofer’s movement, a woofer
mounted in a sealed enclosure will
handle more power than a woofer
mounted in other enclosure type.
Sealed enclosures provide more
accurate sonic reproduction than
other enclosure types, so they are
well suited to all types of music.
Sealed-enclosure construction
is straightforward and there are
many prefabricated sealed
enclosures available. An optimum
sealed enclosure is always smaller
than other types of enclosures opti-
mized for a particular speaker, so it
requires the least amount of space
inside the vehicle.
Vented enclosures provide better
efficiency in the 40Hz – 50Hz range
but this efficiency comes at the
expense of sound in the lowest
octave (below 40Hz) and at the
expense of some control and
power handling. If you are using a
small amplifier, a vented box will
provide more bass output from less
power. Vented enclosures are also
well suited to a variety of music
types. Because vented enclosures
require the volume of the enclosure
and the size of the port to have a
specific relationship with the
characteristics of the woofer, the
enclosure must be built exactly to
the specifications provided. While
there are some prefabricated
vented boxes available, matching a
prefabricated box to a particular
woofer is difficult. If you wish to
use a vented enclosure, we strong-
ly recommend having your author-
ized JBL dealer build it, or at least
verify that your design is correct
if you wish to build it yourself.
An optimum vented enclosure is
always larger than the optimum
sealed box for the same woofer
and will require more space inside
the vehicle.
Bandpass enclosures often provide
the greatest output available from
any amplifier/subwoofer combina-
tion, albeit at the expense of sonic
accuracy. If sheer SPL (sound
pressure level) is what you desire
most, choose a bandpass enclo-
sure. Because bandpass-enclosure
design is tricky, using a computer
and enclosure-design software is
necessary. If you are an experi-
enced installer or have some
woodworking skills, you may wish
to build the enclosure described in
the “Specifications” chart in this
manual. Fortunately, however, there
are many prefabricated bandpass
boxes available and they are all
optimized to extract the greatest
possible output from any woofer.
Be aware that bandpass enclo-
sures can be quite large and may
require a lot of space inside your
vehicle.