Jbl LC-S1050W, LC-S1250W User Manual

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.

Subwoofer

JBL Consumer Products

250 Crossways Park Drive, Woodbury, NY 11797

1-800-336-4JBL (4525) (USA only)

www.jbl.com

2000 JBL, Incorporated

JBL is a registered trademark of JBL, Incorporated.

Part No. 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

RevcFsVas

Qms

Qes

Qts

Mms

Levc

Sealed-Enclosure Specifications

Enclosure Volume

Vented-Enclosure Specifications

Enclosure Volume

Port Diameter

Port Length

Bandpass-Enclosure Specifications

Sealed-Chamber Volume

Vented-Chamber Volume

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)