JBL Media SUB-2000 Service manual

MultiMedia Series Loudspeakers

Media Sub2000

Service Manual

JBL Consumer Products

250 Crossways Park Dr.

Woodbury, New York 11797

- CONTENTS -

SPECIFICATIONS & TEST PROCEDURE……………….….………..1

OPERATIONS & CONNECTIONS……..……..……………...………..2

SERVICE BULLETIN….………..…………….….……………………..3

AMPLIFIER BLOCK DIAGRAM.…………….……..……..…………..4

WIRING DIAGRAM ….………..…………….…..…..……………..5

P.C.B. DRAWINGS….………..…………….………..…..……………..6

VOLTAGE CHART….………..……………………...…..……………..7

EXPLODED VIEW.………..…………….……………..….…………....8

IC DIAGRAMS………………..…………….……….………………….9

MECHANICAL PARTS LIST ..………………………………….…….10

ELECTRICAL PARTS LIST ..………………………………….…..….11

SCHEMATICS ………..……………………..…………………..….13

PACKING ……………….……………………..………….………….14

Media Sub2000 Specifications

1

Max Power Output 35 watts (@ 1% THD)

Frequency Response 50Hz – 120Hz

Input Sensitivity 3V Maximum

Input Impedance 10k ohms

Signal Input Jack Stereo Mini-Connector (1/8”)

Signal Output Jack Stereo Mini-Connector (1/8”)

Dimensions (H x W x D) 9 5/8 x 5 ¼ x 10 ¾”

(244 x 133 x 273mm)

Weight 7.0 lbs. /3.2kg

TEST PROCEDURE

Media Sub2000

Frequency 20Hz – 600Hz

Input Voltage 0.175V

Volume Maximum

General Function

1. Assure Level control volume is Maximum (full CW)

2. Using sine wave generator sweep unit to range of above frequencies

3. Listen to driver and cabinet for rattles, clicks, buzzes, or other unusual noises

2

Service Bulletin

3

Service Bulletin JBL9802 - May 1998 This is considered a Major repair

To: All JBL Service Centers

Model: Media Sub2000 Powered Subwoofer

Subject: False Triggering

In the event you receive a Media Sub2000 with the complaint: “the subwoofer never shuts off”, or “the
unit cycles on & off by itself with no input signal”, perform the following modification to raise the input
threshold of the subwoofer amplifier:

Procedure:

1) Turn the unit upside-down and remove the (8) mounting screws on the bottom plate. This includes the (2)
deeply recessed screws near the center of the plate. Then remove the (2) smaller screws holding the
black input plate to the end of the cabinet.

2) Pull the plate and amplifier up and out the cabinet.

3) Unplug all (3) molex connectors, and remove the (2) small screws holding the input plate onto the
amplifier PCB; remove the input plate.

4) To gain access to the components, remove the (2) remaining small screws holding the PCB to the bottom
plate and detach it from the plate.

5) Locate C351 - 100pf SMD cap. Replace with 470 pf part, (JBL part #CP1885). See drawing.

6) Locate R348 - 330KΩ SMD resistor. Replace with 100kΩ part, (JBL part #RS2043).

7) Locate Diode D351. Solder a 10KΩ resistor (JBL part #RS2042) in parallel with the diode.

8) Reassemble and replace the amplifier assembly into the cabinet in the reverse order , making sure all
connectors and screws are replaced.* When re-attaching the input plate make sure both ground
terminals are attached to the screw.

9) Test unit and assure that the subwoofer stays in the standby mode with no input signal, and comes out of
protection with a 50 Hz, 50 mV input signal.

Model Serial number

120V

Media

Sub2000

Media

Sub2000

AC0029-10001

to
AC0029-11300
AC0029-11301

and above

Serial number

230V

AC0030-01001

and above

* When replacing the final two screws in the
center of the bottom plate, because of the
design you cannot drop the screws into each
cavity and expect the screws to align with the
holes.
With a Philips screwdriver well fitted to the
screw head, you may either use a magnetized
screwdriver and lower the tip (with screw)
carefully down into the cavity to align; OR
turn the subwoofer right-side up and insert the
tip with screw up into the cavity.

Status Action

False Triggering Change value of C351 and R348; add 10K

resistor in parallel with D351

Factory

Modification

NONE REQUIRED

Ω

JBL Incorporated 250 Crossways Park Dr. Woodbury, New York 11797 [phone]