LS CENTER - JBL Audio Service Manual (repair manual)

ACOUSTIC & ELECTRICAL SPECIFICATIONS:
• Nominal Impedance

6 Ohms

• Max Amp Power

150 Watts*

• Frequency Response

50Hz – 40kHz (–10dB)
85Hz – 38kHz (–3dB)

• Sensitivity

88dB (2.83V @ 1 meter)

• Crossover Frequencies

2.5kHz, 9kHz; 24dB/Octave

SYSTEM COMPONENTS:
• Cabinet

LS Center (Not for Sale)

• Grille Ass’y

P07950000

• Low-Frequency Transducer

Dual 6-1/2" (203mm) PolyPlas

™

,

shielded; U00670001

DC Resistance

11.5 Ohms, ±10%

• High-Frequency Transducer

2" (51mm) Pure-titanium 
compression driver, shielded;
U00600000

DC Resistance

3.9 Ohms, ±10%

• UHF Transducer

3/4" (19mm) Polyester-film,
shielded; U00700001

DC Resistance

6.9 Ohms, ±10%

• Crossover Network 

P05750025

AURAL SWEEP TEST SPECIFICATIONS:
• System Aural Sweep Test

6.0V Input 50Hz to 20kHz

• L.F. Aural Sweep Test

5.0V Input 50Hz to 3kHz

• H.F. Aural Sweep Test

1.0V Input 2kHz to 10kHz

• U.H.F. Aural Sweep Test

1.0V Input 8kHz to 20kHz

PHYSICAL SPECIFICATIONS:
• Dimensions 

8-1/2" x 26-1/2" x 9-1/4"

(H x W x D)

(217mm x 672mm x 235mm)

• Dimensions (with feet pad)

9" x 26-1/2" x 9-1/4"

(H x W x D)

(230mm x 672mm x 235mm)

• Weight

31.7 lb/14.4kg (each)

WARRANTY:
• Refer to Warranty Statement packed with each product.
* The maximum recommended amplifier power rating will ensure 

proper system headroom to allow for occasional peaks. We do not 
recommend sustained operation at these maximum power levels.

7/08

Harman Consumer Group, Inc., 250 Crossways Park Drive, Woodbury, New York 11797

Release Date 2008     
Discontinued Date XXXX

Legend on Page 2

Blue +

Black -

Red +

Black -

Black +

Orange -

UHF TRANSDUCER

U00700001

HIGH-FREQUENCY

TRANSDUCER

U00600000

LOW-FREQUENCY

TRANSDUCER 2

U00670001

CROSSOVER NETWORK

P05750025

Black +

Yellow -

Green +

Green +

Black -

Black -

LOW-FREQUENCY

TRANSDUCER 1

U00670001

TERMINAL CUP

WTH BINDING POSTS

P05930002

.205

.110

C1

8.2μF

100v

C7

16μF

100v

C8

0.01μF

100v

C6

0.01μF

100v

C5

3.0μF

100v

C9

6.2μF

100v

C11

0.56μF

100v

C12

1.6μF

100v

C10

0.01μF

100v

C2

1.0μF

100v

C3

16μF

100v

C4

0.01μF

100v

L1

2.0mH

L3

0.39mH

L4

0.13mH

L5

0.13mH

L2

0.56mH

R1

8.2

Ω

10W

R2

5.1

Ω

10W

R4

7.5

Ω

5W

R3

3.9

Ω

10W

.110

.110

Orange 350mm

Black 350mm

Yellow 400mm

Black 400mm

Black 300mm

Green 500mm

300mm

500mm

.110

.205

.205

.205

33

28

16

31

15

8

11

7

18

2

10

23

5

9

1

30

4

22

29

6

24

12

20

25

17

21

13

26

3

32

19

14

27

26

7/08

Harman Consumer Group, Inc., 250 Crossways Park Drive, Woodbury, New York 11797

Screw, LF/UHF Faceplate 3 x 12PA

4

Screw, Woofer 4 x 25FA

8

Screw, Crossover Network 3 x 20BA

11

Screw, Terminal Cup 3 x 15BA

4

29 P07980000

Grille Cup

8

30 P08170000

Gasket, UHF

1

31 Not for Sale

Label

1

32 P08660000

Foot

4

33 P05930002

Terminal Cup w/Binding Posts

1

34 Visit www.jbl.com

LS series Owner’s Manual

1

35 P00490002

Warranty Card

1

36 M00050020

Spike Foot Set

1

37 M00050021

Coaster Set

1

38 M00050019

Packing Set

1

39 P08540000

Outer Carton

1

1

U00700001

UHF Tweeter

1

2

U00600000

HF Tweeter

1

3

U00670001

6–1/2" Woofer

2

4, 5

M00050014

LF/UHF Faceplate w/Gasket

1

6 –12

M00050015

HF Horn Assembly

1

13,14

M00050016

Trim Ring, Woofer w/Felt Gasket

2

15

Not for Sale

Label

1

16

Not for Sale

Label

1

17

P07950000

Front Grille

1

18

Not for Sale

LS Center Cabinet

1

19

P02780000

Insert Nut

4

20

P05750025

Crossover Network

1

21,22

P08160001

JBL Logo

1

23–28

M00050018

Screw Set Includes the Following:

1

Screw, UHF #6-32 x 3/8BM

4

Screw, LF Horn 4 x 20BA

6

1) Remove the grille.
2) Access to the woofer and crossover network is accomplished by gently prying the woofer trim ring out of the counterbore, which is attached with a friction fit, using a small, flat-blade screw-

driver or similar tool. The four Phillips screws will then be visible.

3) Access to the HF/UHF sections is accomplished by first extracting the upper four rubber grille retainers. This can be accomplished by a) inserting a long screw with coarse threads into the cup

hole, thread the screw and extract the cup or b) carefully pulling them out of their cavities with long-nosed pliers or a similar tool. It’s possible each grille cup could be damaged since the cups
are affixed with RTV (a silicon seal). Each cavity should be cleaned out with a 1/4" drill bit before the Phillips head screw is turned. (Power tools are not recommended here). Remove the four
screws, then pull off the faceplate w/UHF driver attached to it.

4) Access LF, UHF tweeter or crossover network as needed.
5) Woofer Replacement: Make sure the woofer is exactly centered in the counterbore, otherwise the trim ring will not fit in place.