Read JBL LC-S 1250w User Guide / Operation Manual online
Loud + Clear subwoofers are optimized to perform best in
small, sealed, vented and prefabricated bandpass enclosures.
While infinite-baffle mounting of Loud + Clear subs is
possible, power handling will be greatly compromised
because there will be 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
Loud + Clear subwoofers.
You should choose an enclosure 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
woofer movement, a woofer mounted in a sealed enclosure
will handle more power than a woofer mounted in another
enclosure type. Sealed enclosures also 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 optimized 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 to the characteristics of the woofer, they
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 strongly recommend having
your authorized 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 combination, albeit
at the expense of sonic accuracy. If sheer SPL (sound
pressure level) is what you desire most, choose a bandpass
enclosure. Because bandpass-enclosure design is tricky,
using a computer and enclosure-design software is
necessary. If you are an experienced installer or have some
woodworking skill, 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 enclosures can be quite large and may
require a lot of space inside your vehicle.
Choosing an Enclosure
Thank you for purchasing a JBL Loud + Clear subwoofer.
Subwoofer installation often requires woodworking skills
and some experience disassembling and reassembling
automotive interiors. If you lack the necessary tools or
know-how, have your subwoofer installed by an authorized
JBL dealer.
Warning!
Playing loud music in an
automobile can permanently
damage your hearing as well as
hinder your ability to hear traffic. We
recommend 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.
S
u
b
w
o
o
f
e
r
Subwoofer
JBL Con
sum
er Pr
od
u
cts
250 Cr
ossways P
ark Drive
, W
oodbury
, NY 11
7
9
7
1-800-336-4JBL (4525) (U
S
A
only)
www
.jbl.com
©
2000 J
B
L, In
corpor
ated
JBL is a r
egister
ed tr
ad
em
ark o
f JBL, In
corpor
ated
.
P
art N
o. LC-S1050/1250OM 1/00
RECYCLABLE
LC-S1250w
120W
RMS,
480W
peak
93dB
38Hz
–
500Hz
5"
(127mm)
10-7/8"
(277mm)
4
Ohms
3.45
Ohms
27.4Hz
109
Liters
3.18
0.37
0.33
109.23g
2.23mH
1.25
cu.
ft.
(35.88
Liters)
1.75
cu.
ft.
(49.54
Liters)
4"
(101.6mm)
10-3/4"
(273mm)
1.25
cu.
ft.
(35.88
Liters)
1
cu.
ft.
(28.31
Liters)
4"
(101.6mm)
6"
(152.4mm)
Specifications
Power
Handling
Sensitivity
(2.83V
,
1m)
Frequency
Response
Mounting
Depth
Cut-out
Diameter
Thiele
and
Small
Parameters
Nominal
Impedance
Revc
Fs
Va
s
Qms
Qes
Qts
Mms
Levc
Sealed-Enclosure
Specifications
Enclosure
V
o
lume
V
ented-Enclosure
Specifications
Enclosure
V
o
lume
Port
Diameter
Port
Length
Bandpass-Enclosure
Specifications
Sealed-Chamber
V
olume
V
ented-Chamber
V
olume
Port
Diameter
Port
Length
LC-S1050w
100W
RMS,
400W
peak
92dB
38Hz
–
800Hz
4-9/16"
(116mm)
9"
(229mm)
4
Ohms
3.52
Ohms
29.5Hz
71
Liters
4.39
0.29
0.268
74.99g
2.02mH
1
cu.
ft.
(28.31
Liters)
1.5
cu.
ft.
(42.46
Liters)
3"
(76.2mm)
7"
(177.8mm)
1
cu.
ft.
(28.31
Liters)
.7
cu.
ft.
(19.82
Liters)
4"
(101.6mm)
8"
(203.2mm)
Display