JBL BASSWAVE Service Manual ▷ View online
4
Powered Subwoofer
BASS2/BASSWAVE
TEST PROCEDURES
Equipment needed:
n
Functional/signal generator
n
True RMS Multimeter
n
Integrated amplifier
n
Cables - line level (RCA) and speaker cables
n
RCA Y-cable
General Function
UUT = Unit Under Test
UUT = Unit Under Test
1.
Connect both right and left line level inputs (RCA)
to signal generator and UUT. Assure input
button is in depressed position. Use Y-cable if
necessary from mono source.
2.
Turn on generator, adjust to 50 mV, 50 Hz
. Plug
in UUT, turn level control full clockwise.
3.
Green LED should light, immediate bass response
should be heard and felt from port tube openings.
4.
Turn off generator, unplug unit, disconnect RCA
cables.
5.
Connect two pair of speaker cables to high level
input terminal on UUT. Assure input button is in
extended (out) position. Cables should be
connected to an integrated amplifier fed by the signal
generator. Observe polarity of speaker cables.
6.
Turn on generator and adjust so that speaker level
output is 2.0V, 50 Hz
. Plug in UUT, turn level
control full clockwise.
7.
Green LED should light, immediate bass response
should be heard and felt from port tube openings.
Sweep Function
1.
Connect both right and left line level inputs (RCA) to
signal generator and UUT. Assure input button is
in depressed position. Use Y-cable if necessary
from mono source.
2.
Turn on generator, adjust to 50 mV. Plug in UUT,
turn level control full clockwise.
3.
Green LED should light, immediate bass response
should be heard and felt from port tube openings.
4.
Sweep generator from 20 Hz to 300 Hz. Listen to
the cabinet and drivers for any rattles, clicks,
buzzes or any other noises. If any unusual noises
are heard, remove driver and test.
Driver Function
1.
Follow instructions on page 2 ( To Access Lower
Woofer ).
2.
Check DC resistance of driver; it should be
approximately 5.2 ohms. Upper (non-removable)
driver can be checked by disconnecting both the
wires to the amplifier and the lower driver, then
connecting the test meter to the wires.
3.
Connect a pair of speaker cables to driver terminals.
Cables should be connected to an integrated
amplifier fed by a signal generator. Turn on
generator and adjust so that speaker level output
is 4.0V .
4.
Sweep generator from 20 Hz to 1KHz
. Listen to
driver for any rubbing, buzzing, or other unusual
noises.
* The upper woofer in non-serviceable. Order
replacement cabinet/upper driver assy.
(Part#BASSWAVEENCLKIT). Also cone/diaphram
kits not available, defective drivers should be
replaced.
Service Notes/Revisions
In the event you receive a unit with the complaint that
In the event you receive a unit with the complaint that
the unit shuts down after it is on for a while", usually
about 10-15 minutes. (Verify the R46 has not been
changed with a jumper already; then proceed with
modification of the amplifier unit).
This should be performed on units with circuit board
marked Rev. 001 to Rev. 003.
If you have found output devices Q4 or Q5 shorted,
replace with matched pairs only. This is critical for
proper amplifier operation.
Procedure: Locate R46 (33 ohm) and replace it with a
22 gauge jumper wire. After verifying normal turn-on,
load the amp with a 4 ohm watt resistor and apply a
70 Hz, 200 mV signal to one RCA input jack. Let the
amp run for about 20 minutes to confirm the amp no
longer shuts down.
5
Powered Subwoofer
BASS2/BASSWAVE
Additional Service Notes/Revisions
Customers who complain of a low level distortion
Customers who complain of a low level distortion
heard only during very quiet musical passages, or
experience erratic/inconsistent turn-on performance
may need to have their units modified as follows:
1 . Remove jumper wire JW12.
2. Change resistor R24 to a 22k ohm, 5%, 1/8W.
1 . Remove jumper wire JW12.
2. Change resistor R24 to a 22k ohm, 5%, 1/8W.
(JBL part# HM185-02202-00).
3 . Change capacitor C19 to a .0047 uf cap.
(JBL part# 3679472120).
4 . Cut trace at SW1 (middle pin which runs to JW12).
5 . Add 2" insulated jumper wire from SW1 (middle
5 . Add 2" insulated jumper wire from SW1 (middle
pin) to right-hand side of JW12. Route this jumper
away from the four large diodes.
6 . Add an uninsulated jumper from the left-hand side
of JW12 to the ground trace which runs just to
the right of it.
Serial numbers below should already be modified.
100v
120v
230v
JSEKE10988
and above
JSEKD13486
and above
JSELD027239
and above
JSEKF20034
and above
JSELF020498
and above
Early versions of the units ending with serial #JSELD
024124 had a 18VDC output jack; later versions are
missing this. It’s presence or absence does not affect
subwoofer operation in any way.
Early versions of the units below serial # JSELD
024125 will cycle into a standby mode when the
signal source is absent after a predetermined time;
the green LED turns OFF when this happens on the
120 volt version, the LED cycles to RED on the 230
volt versions. The unit’s sensitivity to input signals
was increased on serial # JSELD 024125 and above;
these units may stay ON, even when the input signal
is absent. This is a normal condition, and does not
compromise the safety, integrity, or dependability of
the product in any way. The standby condition that
took place on earlier versions was an electronic
muting, and both versions draw the same amount of
power at all times, whether muted or ON.
NOTE: If a customer (of a later revision) is insistent
that the auto-mute feature work on his subwoofer, an
easy way to accomplish this is to use the speaker
level (high level) inputs on the unit in lieu of the RCA
jacks.
WIRING DIAGRAM
6
Powered Subwoofer
BASS2/BASSWAVE
ELECTRICAL PARTS LIST
Ref. Number Part Number
Description
Quantity
Capacitors
C1
HM14-0682
0.022
µ
f, 5%, 50V
1
C3, 4
HM14-0600
10
µ
f, 50V, RL
2
C5
14-0744
EL, 4.7
µ
f, 50V, RD
1
C6, 7
C14-0646
EL, 100
µ
f, 10V, RAD
2
C9
14-0603
EL, 100UF, 20%, 25V, RD
1
C12
HM14-0581
SF, 0.047
µ
f, 5%, 50V
1
C13
HM14-0727
CD, 100
ρ
f, 5%, 100V
1
C14
14-0632
CD, 10
ρ
f, 10%, 500V
1
C15
HM14-0740
CD, 470
ρ
f, 5%. 100V, 5E
1
C16
HM14-0592
SF, 0.01
µ
f, 5%, 50V, RAD
1
C17, 18
282778-001
EL, 4700
µ
f, 50V, RAD
2
C19
HM14-0677
SF, 0.0018
µ
f, 5%, 50V
1
C20
HM14-0582
SF, 0.1
µ
f, 5%, 50V
1
Diodes
CR1, 2, 3, 4
13-0719
RECT, 3A, 200V 1N5402
4
CR5, 8, 11
C13-0482
GP, 1N4148
3
CR6, 7
13-0357
ZR, 1N4744A, 15V, 10%, 1W
2
Miscellaneous
CR10 (230V)
283025-002
LED, BI-COLOR, T1, FLH, 230V 1
(120V)
283025-001
LED, GREEN, TI, FLH, 120V
1
J1
282558-001
JACK, 2P, RCA, PCMT, GOLD
1
J2
282646-001
TERM, 4P, PCMT
1
JW1-5, 7-14
99-0183
WIRE, BUSS, 22G, SOLID
2.31ft
R46
SW1
Z100-5003
SWITCH 4 KNOB, K100-1009
1
TH1
S200-0161
POSISTOR, 50C
1
Transistors
Q1
HM13-0413
T0-92, NPN, 2N3904
1
Q2
13-0632
TIP31C, NPN, 100V
1
Q3
13-0633
TIP32C, PNP, 100V
1
Q4
S225-1515
TIP36C, PNP, SGS
1
Q5
S225-1517
TIP35C, NPN, SGS
1
Q6
13-0270
FET, J112, N-CH, T0-92
1
Resistors
R2
HM185-1000-00
0
Ω
, 5%, 1/8W
1
R3
50180-019
MF, 150k, 1%, 1/8W
1
R6
HM185-01001-00 CF, 1k, 5%,1/8W
1
R7
50392-020
CF, 430
Ω
, 5%, 1/8W
1
R8, 35
C185-03301-00
CF, 3.3k, 5%, 1/8W
2
R9, 10
282789-001
MF, 470
Ω
, 5%, 3W, SWL
2
R11, 14, 19
50180-135
MF, 49.9k, 1%, 1/8W
3
Ref. Number Part Number
Description
Quantity
R12, 13, 16, 17 307972-001
MF, 511-OHM, 1%, 1/2W
4
R15
282822-001
MF, 12.1-OHM, 1%, 1/4W
1
R18
282833-001
MF, 16.5
Ω
, 1%, 1/4W
1
R20, 23
C185-010000-00
CF, 100
Ω
, 5%, 1/8W
2
R21, 34
185-03303-00
CF, 33Ok, 5%, 1/6W
2
R22
C185-02200-00
CF, 220
Ω
, 5%, 1/8W
1
R41
185-04702-00
CF, 47k, 5%, 1/6W
1
R24
185-04702-00
CF, 20k, 5%, 1/8W
1
R25
HM185-02201-00 CF, 47k, 5%, 1/6W
1
R26
50180-177
MF, 147k, 1%, 1/8W
1
R27
HM185-01102-00 CF, 11k, 5%, 1/8W
1
R28
HM185-08200-00 CF, 820
Ω
, 5%, 1/8W
1
R29, 32
HM184-01001-00 MF, 1k, 1%, 1/4W
2
R30
187-00057-00
WW, 33
Ω
, 5%, 3W
1
R31
282809-001
MF, 330
Ω,
5%, 3W, SML
1
R33, 39
HM185-02202-00 CF, 22k, 5%, 1/8W
2
R36
185-01005-00
MF, 10MEG, 5%, 1/6W
1
R37
VP70007-185
1.8MEG, 1/8W
1
R38, 40
HM185-01002-00 CF, 10k, 5%, 1/8W
2
R42
HM185-01004-00 CF, 1MEG, 5%, 1/8W
1
R45
181-02201-00
CF, 2.2k, 5%, 1/4W
1
R44, 47
282809-001
MF, 330
Ω
, 5%, 3W, SML
2
Transformers
T1
282459-004
TRANSFORMER 120V 60Hz
1
T1
282459-002
TRANSFORMER 230V 50Hz
1
T1
282459-003
TRANSFORMER 100V 50/60Hz 1
Integrated Circuits
U1
13-0217
TL074, QUAD, OP-AMP
1
U2
13-0304
TL072CP, OP-AMP, DUAL
1
BASS2/BASSWAVE PARTS LIST
7
Powered Subwoofer
BASS2/BASSWAVE
INTEGRATED CIRCUIT DIAGRAMS
U1 - TL074 OP AMP
(1/4 SHOWN)
OUTPUT 3
V+
V-
OUTPUT 2
-INPUT 1
-INPUT 4
-INPUT 2
-INPUT 3
+INPUT 1
+INPUT 4
+INPUT 2
+INPUT 3
OUTPUT 1
OUTPUT 4
14
11
1
4
13
10
2
5
12
9
3
6
8
7
1
2
3
4
-INPUT
+INPUT
OUTPUT
V+
GND
V+
V-
-INPUT
+INPUT
OUTPUT
V+
B OUTPUT
B -INPUT
B +INPUT
V-
A +INPUT
A -INPUT
A OUTPUT
A
B
8
1
7
2
6
3
5
4
U2 - TL072CP OP AMP
(1/2 SHOWN)
Q2
Q3
Q4
Q5
- TIP 31C
- TIP 32C
- TIP 36C
- TIP 35C
B C E
Click on the first or last page to see other BASSWAVE service manuals if exist.