JBL PB-12 Service manual

PowerBass™ Series

PB12

Powered Subwoofer

Service Manual

JBL Consumer Products
250 Crossways Park Dr.

Woodbury, New York 11797 Rev10 2/2004

PB12 TABLE OF CONTENTS

2

Safety Information ………………………………………………….……….3
Basic Specifications ……………………………..………………………….4
Detailed Specifications ……………………………………….…………….5
Controls and their Function………….……..……………………………….6
Connections …………………….……………………………………………7
Operation ……………………………………………………………………10
Troubleshooting…………………………………………….……………….11
Test Setup and Procedure …………………………………………..…….12
Service Bulletin JBL 2001-03 ……………………….………………… ….1 3
Service Bulletin JBL 2001-04 …………………………………….……….14
Service Bulletin JBL 2001-05 ……………………………….…………….17
Service Bulletin JBL 2001-07 ……………………………….…………….18
Service Bulletin JBL 2001-08 ……………………………….…………….19
Tech Tip JBLTT2003-04…………………………………..……………….20
Exploded View/Packaging.………………………… …………………. .…. 21
Amplifier Exploded View ………………………………………….……….22
Amplifier Faceplate/Access…………………………………………..……23
Integrated Circuit Diagrams……………………………………………….24
Testing Procedures..…………… …………………………………………26
Block Diagram Revision 2…………………………………………………32
Electrical Parts List (PCB version 6.3 – 7.0)…………………………… 33
Electrical Parts List (PCB version 7.2) ……………………………..……37
Electrical Parts List Revision 2…………………………………………….41
Printed Circuit Boards (PCB version 6.3)…………………...……..…….44
Printed Circuit Boards (PCB version 6.4)………..…..……………….….47
Printed Circuit Boards (PCB version 7.2)… …………………………….48
Schematic s Ver sion 1

Preamp (PCB version 6.3)…………………………… …….……….51
Power Amp (PCB version 6.0 -6.3)…….. ………………………….52
Power Amp (PCB version 7.0)…………… …………………..…….53
Preamp (PCB version 7.2)…………………………… ……….…….54
Power Amp (PCB version 7.2)……………………………. …… ….55

Schematics Version 2…………………………………………….. …….… 56

PB12 – DIFFERENCES IN REVISION 1 AND REVISION 2

REVISION 1 REVISION 2

Amplif ier serial number starts with “H A ”

Amplifier faceplate says “Made in Canada”
Amplif ier serial number starts with “A M ”
Black (or silv er) po t ted, non-serv icea ble output module

Output transistors in the open, on a large black heatsink
Large plastic cup enclosing the rear of the amp assembly
Main PCB, bottom, solder-side contains all SMD devices
“Made in Mexico” label on outer part of cabinet

BOTH VERSIONS OF THESE AMPLIFIERS ARE NOT CONSIDERED INTERCHANGEABLE; THEY ARE
NOT A DROP-IN REPLACEMENT IN THE CABINET OF THE OTHER VERSION.

PB12

3

Warning

Any person performing service of this unit will be exposed
to hazardous voltages and the risk of electric shock. It is
assumed that any person who removes the amplifier from
this cabinet has been properly trained in protecting
against avoidable injury and shock. Therefore, any service
procedures are to be performed by qualified service
personal ONLY!

Caution

Before the amplifier is plugged in, be sure its rated
voltage corresponds to the voltage of the AC power
source to be used. Incorrect voltage could cause damage
to the amplifier when the AC power cord is plugged in. Do
not exceed rated voltage by more than 10%: operation
below 90% of rated voltage will cause poor performance
or may shut the unit off.

Leakage/Resistance Check

Before returning the unit to the customer, perform a
leakage or resistance test as follows:

Leakage Current. Connect the unit to its rated power
source. Using an ammeter, measure the current between
the neutral side of the AC supply and chassis ground of
the unit under test. If leakage current exceeds 0.5mA, the
unit is defective. Reverse the polarity of the AC supply
and repeat.

Resistance. Measure the resistance from either side of the
line cord to chassis ground, If it is less than 500k ohms,
the unit is defective.

WARNING! DO NOT return the unit to the customer if it
fails one of these tests until the problem is located and
corrected.

Critical Components

All components identified with the IEC
symbol in the parts list and schematic
diagram designate components in which
safety can be of special significance when

replacing a component identified with. Use
only the replacement parts designated in the parts list or
parts with the same rating of resistance, wattage or voltage.

SAFETY INFORMATION

List of Safety Components
Requiring Exact Replacements

Revision 1 Revision 2 Description

F1 - 80117 093-105202-300 Line Fuse Slo Blo 2.0A
PWRCORD 083-041802-009 250V UL approved

80105 SPT-2 or better with

polarized plug, UL
approved wired with the
hot side to fused side.
Use with factory
replacement panel strain
relief (70305) only.

TRX 042-010053-003 Power Transformer. Use
80116 only factory replacement.

BR RECT BR1 Bridge diode. Use only
50100 052-400080-000 factory replacement.

C1,2 C6,8 Large electrolytic filter
(2200uF 100V) (3300uf 80v) caps. Be sure
30710 034-470745-200 replacement part is at

least the same working
voltage and capacitance
rating.
Also the lead spacing is
important. Incorrect
spacing may cause
premature failure due to
internal cabinet pressure
and vibration.

C10 Does not apply 4.7uF, 100 volt NPE low
30718 df radial.

(On Power amp PCB)

S64AMI Does not apply Power output module.
60302 Use only factory

replacement

Faceplate n/a Use only factory
70325 replacement

Rear Amp Cover 063-531808-000 Use only factory
Does not apply replacement

Inductor Does not apply CMC - Use only factory
80100 replacement

Inductor Does not apply L1 - Use only factory
80121 replacement

Does not apply Inductor L2 - Use only factory

043-300101-000 replacement

Does not apply Inductor L3 - Use only factory

043-700101-000 replacement

PB12

4

g

BASIC SPECIFICATIONS PB12 Subwoofer

Output Power

Driver

Frequency Response

Inputs

Outputs

Low-Pass Frequency

High-Pass Frequency

Dimensions (H x W x D)

Weight

250 watts RMS

12" Woofer

25Hz – Low-Pass Frequency setting

Line Level (option: LFE); Speaker Level

Speaker level fixed frequency 150Hz

Variable from 50Hz – 150Hz

150Hz when using Speaker Level Output

15 1/2" x 15" x 16"
394mm x 381mm x 406mm
(with feet) 17 1/2" x 15" x 16"
445mm x 381mm x 406mm

40 lb/18.2kg

00261-1

Refinements may be made on occasion to existing products without notice but will always meet or exceed original
specifications unless otherwise stated.
PowerBass is a re

istered trademark of JBL, Incorporated.

PB12

5

mits

y

y

@ Sp

q

g

g

g

p

p

p

p

y

p

p

p

p

p

signal applied

emoved

pp

@ Sp

pp

@

pp

@

g

@

condition remova

times the input voltage

p

yp

DETAILED SPECIFICATIONS PB12 Subwoofer

JBL PB12 250W Powered Sub Amp

LINE VOLTAGE Yes/No Hi/Lo Line Nom. Unit Notes

Parameter Specification Unit

Amp Section

Type (Class AB, D, other) D n/a

Load Impedance (speaker) 5.6 Ohms

Rated Output Power (120VAC) 250 Watts

Rated Output Power (230VAC) 250 Watts

THD @ Rated Power 0.3 %

THD @ 1 Watt 0.1 %

DC Offset 10 mV-DC

Damping factor >50 DF

Input Sensitivity

Input Frequency 50 Hz

L&R 240 mVrms

LFE input 240 mVrms

Speaker/Hi Level Input 2.4 Vrms

Signal to Noise

SNR-A-Weighted 90 dBA

SNR-unweighted 85 dBr

SNR rel. 1W-unweighted 65 dBr

Residual Noise Floor 1 mVrms

Residual Noise Floor 1.5 mVrms(max)

Input Impedance

Filters

LP filter 4th order fixed 60-180 Hz

Subsonic filter (HPF) 3rd Order Fixed

LFE Low pass 2nd order 200>LP<1K Hz

HP speaker out connector 200 Hz

Features --

Volume pot Taper (lin/log) LOG --

HP Speaker out YES

Phase switch 0-180 deg

LP Filter defeat switch YES

Input Configuration

Line In (L,R) & LFE

Spkr/Hi Level In YES --

Signal Sensing (ATO)

Auto-Turn-On (yes/no) YES

ATO Input test frequency 50 Hz

ATO Level LFE Input 4 mV

ATO Level Speaker in 50 mV

ATO Turn-on time 5 ms

Auto Mute/ Turn-OFF Time 15 minutes

Power on Delay time 3 sec.

Transients/Pops

ATO Transient 5 mV-peak

Turn-on Transient 50 mV-peak

Turn-off Transient 50 mV-peak

Efficiency 65 %

Stand-by Input Power 24 Watts

Power Cons. @ rated power 234 Watts

Protection

Short Circuit Protection YES

Thermal Protection YES

DC Offset Protection YES

Line Fuse Rating

USA-Domestic 2 Amps Type-T or Slo Blo-250 V

EU 1.25 Am

US 120vac/60Hz Yes 108-132 120 Vrms Normal Operation

EU 230vac/50-60Hz Yes 207-264 230 Vrms Normal operation, MOMS required

Conditions Notes

120 VAC-60 Hz

230 VAC-50 Hz

eaker Outputs

.

ower A-Weighting filter

ower 22k filter

ut 22k filter

=

ut driven onl

"

" Maximum acce

" Maximum acce

lied

eaker Outputs

e-T or Slo Blo-250 V External fuse with UL/SEMKO rated holder

At spkr cable. 150 Watts @ THD < 0.1 % @ 50 Hz

le input driven

le input driven, LFE switch ON

le input driven

Line level inputs must be terminated using 1KOHM

Line level inputs must be terminated using 1KOHM

A Ta

er

Binding post connector L&R

table level.

table level.

Auto turn of time (T) must be 5 > T < 15 Minutes

Nominal Line volta

Maximum allowable input power under nominal

Input voltage and frequency, HOT or COLD

Amplifier should resume operation after short circuit

e 120 VAC

l

Line Input (L, R,LFE) 20K ohms

Speaker/Hi Level Input 4.7K ohms

100 Hz

YES -- functional Dual RCA jack

QA Test

Li

n/a

Nominal

n/a

140 Domestic version onl

130 EU Version onl

22k filter 145 Watts

1

22k filter

0.5

20

Measured at amplifier board

35

Nominal Fre

50

To 150 Watts Sin

±2dB

To 150 Watts Sin

±2dB

To 150 Watts Sin

±2dB

relative to rated

70

relative to rated

70

relative to 1W Out

60

3 Volume @max, using RMS reading

DMM/VOM (or A/P) BW=20 Khz.

3 Volume @max, w/ A/P Swept

Bandpass Measurement (Line freq.+

Nominal

n/a

Nominal

n/a

± 10 2nd order variable + 2nd order fix-24 db/Octave

LFE in

± 10 S

± 10 S

functional

functional Refer to Filter section

functional

functional Disables LP filter, intended for LFE

functional

functional

functional

functional

functional

functional Amp connected and AC on, then input

15 T before muting, after signal is

n/a

2v-

2v-

64

26

240

functional

functional @1/8 max unclipped Power at 1.06

sT

eaker input driven - 4 Ohms

eaker input driven - 8 Ohms

r

AC Power A

4

Speaker Outputs AC Line cycled from OFF to ON

Speaker Outputs AC Line cycled from ON to OFF

@ nom. line voltage

nom. line voltage 150 Watts @ 5.6 Ohms nominal line voltage

Direct short at output

DC present at Speaker Out leads

-

PB12

6

PB12 Subwoofer Controls and Their Function

1. Power - These lights will be red when the unit is

plugged in and not receiving a signal; when the PB12
receives a signal, the lights will cycle to GREEN. If no
signal is received after 10-15 minutes the lights will
cycle back to RED (standby) until a signal is present
again.

2. Level Control - The subwoofer Level Control, PB12,

(located on the rear panel) adjusts the volume of the
subwoofer relative to the rest of the system.

3. LFE/Normal Switch - Ordinarily placed in the Normal

position - but switch to LFE when playing Dolby

®

Digital, DTS®or other digital surround modes - see
page 9.

4. Phase Switch - Changes the subwoofer’s output to

be in phase or 180 degrees out of phase with the
program material.

5. Crossover Frequency - Sets the highest frequency

the subwoofer will reproduce.

6. Line Input - Main Input connection to subwoofer

(preferred).

7. Speaker In Jacks - Main Input connection to

subwoofer when line level, subwoofer, or pre-amp
output connectors are not available, or when a high
pass filter (set at 150Hz) to main loudspeakers is
desired through the Speaker Output Jacks.

8. Speaker Out Jacks - Connected to main

loudspeakers when the Speaker Input Jacks are used.

9. Power Switch - Turns the PB12 on or off.

Rear Panel

Front Panel

R

PB12

7

Speaker Connection

When we designed the PB12
powered subwoofers, our goal
was to offer the user the best
possible performance
combined with the most
flexible and complete
installation options. Please
look over the following three
examples to determine which

description best matches
your system and follow the
corresponding hookup
instructions.

To use the binding-post
speaker terminals with bare
wire, unscrew the collar until
the hole through the center-

post is visible under the collar.
Insert the bare end of the wire

through the hole in the post,
then screw the collar back
down until the connection is
tight. The holes in the center
of the collars are intended for
banana-type connectors.

Dolby Pro Logic (Non-Digital) – Speaker Level

Use this installation method for
Dolby Pro Logic applications
(not Dolby Digital, DTS or other
digital processing), where the
receiver/processor does not
have a subwoofer output or a
volume-controlled preamp
(line-) level output:

Connect your receiver or
amplifier’s front left and right
speaker terminals to the left
and right terminals on the
subwoofer that are marked
“High Level In.” Connect the
left and right terminals on the
subwoofer that are marked
“High Level Out” to the
corresponding terminals on
the back of your front left
and right speakers.

Connect your receiver or
amplifier’s center, left and right
surround-speaker terminals to
the corresponding terminals on
the back of your center, left
and right surround speakers.

PB12

8

Dolby Pro Logic (Non-Digital) – Line Level

Use this installation method for
Dolby Pro Logic applications
(not Dolby Digital, DTS or other
digital processing), where the
receiver/processor is equipped
with a subwoofer output or a
volume-controlled preamp
(line-) level output:

Use RCA-type patch cords
to connect the line-level
subwoofer outputs on your
receiver or amplifier to the line­level inputs on the subwoofer.
IMPORTANT: Make sure that
the LFE toggle switch on the
subwoofer is in the “Normal”
position. Do not use the “LFE”

position with Dolby Pro Logic­only processors.

Note: If your receiver or
amplifier only has one
subwoofer output jack,
then you may connect the
subwoofer output on your
receiver/preamplifier to either
the left or right line-level input
on the subwoofer. It makes no
difference which jack you
choose.

Connect each speaker to
the corresponding speaker
terminals on your receiver or
amplifier.

Make sure your receiver or
processor is configured
cor

rectly: Make sure that the

sub

woofer is configured as

“On.”
Note for advanced users: If

your receiver/processor has
a built-in low-pass crossover
filter for the subwoofer output,
then the LFE switch should be
set to the “LFE” position to
bypass the subwoofer’s
internal crossover.

PB12

9

Dolby Digital or DTS (or Other Digital Surround Mode) Connection

Use this installation method for
Dolby Digital, DTS or other
digital surround processors:

IMPORTANT: Make sure that
the LFE toggle switch on the
subwoofer is in the “LFE”
position. Use the line-level
input jacks for the Low­Frequency Effects channel.
Connect these jacks to the LFE
output or subwoofer output on
your receiver or amplifier.

Note: If your receiver or
amplifier only has one
subwoofer output jack,
then you may connect the
subwoofer output on your
receiver/preamplifier to either
the left or right line-level input
on the subwoofer. It makes no
difference which jack you
choose.

Connect each speaker to
the corresponding speaker
terminals on your receiver
or amplifier.

Make sure that you have
configured your surround­sound processor for
“Subwoofer On” or “LFE On.”
The front left, front right, center
and rear speakers should be
set to “Small” or “Large”
depending on their size and
frequency response. Consult
your receiver’s or processor’s
owner’s manual.

PB12

10

OPERATION

Power

When the unit is plugged in
and the power switch is on and
no signal is received, the LEDs
on the front of the unit will turn
red. When a signal is present,
the LEDs will turn green.

Note: It will take several
minutes for the LEDs to turn
from green to red after the
input signal to the subwoofer is
removed. Due to JBL’s unique,
high-output,

high-efficiency
amplifier design, power
consumption is minimal when
the subwoofer is not receiving
a signal.

The subwoofer Level Control
adjusts the volume of the
subwoofer relative to the rest
of the system. Proper level
adjustments depend on several
variables such as room size,

subwoofer placement, type of
main speakers and listener
position. Adjust the subwoofer
level so that the volume of the
bass information is pleasing
to you.

Level Control

Crossover Adjustments

The Crossover Frequency
Control determines the highest
frequency at

which the

subwoofer reproduces

sounds.
If your main speakers can
comfortably reproduce some
low-frequency sounds, set this
control to a lower frequency
setting, between 50Hz – 100Hz.
This will concentrate the
subwoofer’s efforts on the
ultradeep bass sounds required
by today’s films and music. If
you are using smaller bookshelf
speakers that do not extend to
the lower bass frequencies, set
the low-pass crossover control
to a higher setting, between
120Hz – 150Hz. This control is
not used when the LFE switch
is in the “LFE” position.

LEVEL

CROSSOVER
FREQUENCY

PowerBass PB12

LINE LEVEL IN

+ –

ON OFF

POWER

PowerBass PB12

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

Min

LFE NORMAL

0º 180º

PHASE

50Hz

L R

For LFE use L or R

HIGH
LEVEL

HIGH
LEVEL

OUT

IN

R

L

R

L

150Hz

120V
60Hz

Max

PB12

11

Phase Control

The Phase Control determines
whether the subwoofer’s
piston-like action moves in and
out in phase with the main
speakers or opposite the main
speakers. There is no correct
or incorrect setting. Proper
phase adjustment depends on
several variables such as
subwoofer placement and
listener position. Adjust the

phase switch to maximize bass
output at the listening position.

Remember, every system,
room and listener is different.
There are no right or wrong
settings; this switch offers the
added flexibility to adjust your
subwoofer for optimum
performance for your specific
listening conditions without
having to move your speakers.

If at some time in the future
you happen to rearrange your
listening room and move
your speakers, you should
experiment with the phase
switch in both positions, and
leave it in the position that
maximizes bass performance.

TROUBLESHOOTING

If you used the high-level
(speaker) inputs and there
is no sound from any of the
speakers:

•

Check that receiver/amplifier
is on and a source is playing.

• Check that powered

subwoofer is plugged into
an active electrical outlet
and is switched on.

• Check all wires and

connections between
receiver/amplifier and
speakers. Make sure all wires
are connected. Make sure
none of the speaker wires are
frayed, cut or punctured.

• Review proper operation

of your receiver/amplifier.

If there is low (or no) bass
output:

• Make sure the connections to
the left and right “Speaker
Inputs” have the correct
polarity (+ and –).

• Make sure that the
subwoofer is plugged into an
active electrical outlet and
switched on.

• Adjust the crossover point.

• Flip the Phase Control switch
to the opposite position.

• If you are using a Dolby
Digital/DTS receiver or
processor, make sure that the
subwoofer adjustments on
the receiver/processor are
set up correctly.

• Slowly turn the Level
Control clockwise until you
begin to hear the desired
amount of bass.

If you used the line-level
inputs and there is no sound
from the subwoofer:

•

Check that receiver/amplifier
is on and a source is playing.

• Check that powered
subwoofer is plugged into an
active electrical outlet and is
switched on.

• Check all wires and
connections between
receiver/ amplifier and
subwoofer. Make sure all
wires are connected. Make
sure none of the wires are
frayed, cut or punctured.

• Review proper operation of
your receiver/amplifier.

• Slowly turn the Level
Control clockwise until you
begin to hear the desired
amount of bass.

• Make sure that you have
configured your receiver/
processor so that the
subwoofer/LFE output is on.

PB12

12

PB12 TEST SETUP AND PROCEDURE

General Function
UUT = Unit Under Test

1. Connect one line level input cable (RCA) from signal generator to either Right or Left Level input on UUT. VOLUME
control should be full conterclockwise. Make sure the LFE/Normal switch is in the NORMAL position.

2. Tur n on generator, adjust to

100mV, 50Hz.

3. Plug in UUT; Turn Main Power switch ON. LED’s on the front panel may be either Red or Green. Turn VOLUME
control full clockwise. Low Pass control should be set fully clockwise (150Hz).

4. LED should turn Green; immediately bass response should be heard and felt from port tube opening.

5. Tur n off generator, turn VOLUME control fully counterclockwise, disconnect RCA cables.

6. Connect one pair of speaker cables to either high level input terminal on UUT. Cables should be connected to an
integrated amplifier fed by the signal generator.

7. Tur n on generator and adjust so that speaker level output is

1.0V, 50Hz. Turn VOLUME control full clockwise.

8. Green LED should light, immediate bass response should be heard and felt from the port tube opening.

Sweep Function

1. Follow steps 1-4 above, using a sweep generator as a signal source.

2. Sweep generator from 20Hz to 300Hz. 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. Remove driver from cabinet; detach + and – wire clips.

2. Check DC resistance of driver; it should be 4.8 ohms.

3. Connect a pair of speaker cables to driver terminals. Cables should be connected to an integrated amplifier fed by a
signal generator and adjust so that speaker level output is 5.0V.

4. Sweep generator from 20Hz to 1kHz. Listen to driver for any rubbing, buzzing, or other unusual noises.

CD PLAYER

PRE AMP

AMPLIFIER

AC VOLT

SPEAKER

LEVEL

METER (6V)

LINE LEVEL

UNDER TEST

FROM

LINE-LEVEL

SOURCE

PB12

SPEAKER

OUTPUT

FROM

AMPLIFIER

LEVEL

Min Max

PHASE

CROSSOVER
FREQUENCY

50 Hz 150 Hz

PowerBass PB12

LR

LINE LEVEL IN

FOR LFE USE L or R

LFE

NORMAL

180

0

L

HIGH
LIVEL

IN
R

L

HIGH
LIVEL
OUT

R

00229

PB12

13

Service Bulletin

Service Bulletin JBL2001-03 Rev1 – January 2002 This is considered a Minor repair

To: All JBL Service Centers

Models: PB10, PB12 (Revision 1 only)*

Subject: Unit Will Not Switch to Standby Mode

When the power cord of the PB series subwoofer is plugged into a wall outlet (and for the PB12 only, the power

switch is on), and an audio signal is present, the LED’s on the cabinet face will turn green, indicating the

subwoofer is in the ON mode. With the audio signal removed, it will take 10 - 15 minutes for the LEDs to turn

from green to red, indicating the subwoofer is now in the STANDBY mode. Power consumption is minimal in this

mode.

In the event you receive a PB10 or PB12 subwoofer with the complaint: “The unit will not switch to

standby mode, even when the audio signal is removed” (indicated by the subwoofer’s green LED’s

remaining on), perform the following modification:

1) Set the unit on a padded surface and remove all external cables.

2) On the amplifier faceplate, remove the (10) Phillips mounting screws around the perimeter.

3) Remove the amplifier assembly from the enclosure. If the amp is turned and supported correctly, no other

connectors need to be unplugged.

4) Locate Zener Diode D10 and Resistor R42 (22kΩ). See illustration. These parts must be “swapped”, i.e.,

R42 soldered into the D10 location, and D10 soldered into the R42 location. VERY IMPORTANT: Observe

polarity on D10 in new location.

5) Replace amplifier; test subwoofer to assure the unit goes into the standby mode 10 - 15 minutes after

removing the Audio input signal.

Mode l S e r i al num be r S ta tus Ac ti on

PB10 *

PB12 *

Al l ser i al number s

af f ect ed

Unit may not switch to Standby mode

Swap locations:

Zener Diode D10,

Resistor R42 (22kΩ).

Observe D10 polarity.

* Revision 1 of the PB10/12: Amplifier faceplate says “Made in Canada”; Amplifier serial number starts with “AM”

Black (or silver) potted, non-serviceable S53/64AMI output module. PB10 only – No Power switch

14

Service Bulletin

Service Bulletin JBL2001-04 Rev2 – February 2003 This is considered a Minor repair

To: All JBL Service Centers

Models: PB10, PB12 (Revision 1 only)*

Subject: Hum, Buzz or “Thumping”

In the event you receive a PB10 or PB12 subwoofer complaint: “There is an audible hum or buzz”, or the
subwoofer “thumps” or “pops” every 10 seconds, then review the conditions below to determine the most
effective solution:

A) Audible Hum with unit on, Green LED is ON, hum disappears completely when the connecting input cables (RCA or

Speaker-Level) are disconnected:

Very long runs of line-level input cables, particularly in parallel with AC power cords, may induce hum in the

audio cables. Check audio cables for defects, broken ground connections, or replace low quality cables. Try
plugging the AC power cord from the subwoofer into a different AC service outlet other than the outlet the rest

B) Mild Audible Hum under all circumstances when power cord is plugged in outlet. Hum level does not change

This may be a mechanical hum caused by the power transformer. Note that a slight hum, within design limits,

C) Loud Hum, under all circumstances. It may be louder when LED’s are Green vs. Red ; it may be affected by the

Reset the digital subwoofer amplifier by unplugging the AC power cord. Wait 30 seconds, then plug the cord

For #B only - If the unit still does not function correctly, then check and replace main Power Supply

Both Value and df should be checked, with a GenRad model 1657 Digibridge or equivalent
Value should be the rating listed below, within this tolerance:
A df value of higher than 15% (.15) should be considered defective.

PB10
PB12

For #C only - If the unit still does not function correctly, then replace Power Amp Module S53/64AMI as per
instructions below: PB10: JBL part# 60301

1) Set the unit on a padded surface and remove all external cables.

2) On the amplifier faceplate, remove the (10) Phillips mounting screws around the perimeter.

3) Remove the amplifier assembly from the enclosure. If the amp is supported correctly, no other connectors need to

4) Locate the Power Amp Module S53/64AMI, see location on the following page. It is the large black or gray

5) Replace the amplifier assembly back into the cabinet; replace the screws.

6) Test the unit and confirm the original problem has been corrected. NOTE: THE PB10/12 REVISION 1 AMPLIFIER

of the audio equipment is plugged into.

whether the LED’s are Red or Green, or input cables are connected or disconnected. Level control adjustments do
not change the hum level.

may be noticeable in a very quiet room, when you are close to the unit. This is acceptable within the PB10/12’s
product and price category to most customers, but not to others. If the mechanical hum is unacceptable to the
customer, then replace Power Transformer. PB10: JBL part# 80135. PB12: JBL part# 80116

position of the Level control. The subwoofer may “thump” or “pop” approximately every 10 seconds.

back in. Repeat this 2-3 times if necessary.

capacitors C1 and C2.

+80/-20 %

4700 µF 50v 105c
2200 µF 100v 105c

be unplugged.

component with a metal case. On the solder side of the circuit board are 28 soldered connections. NOTE: See
special handling instructions for S53/64AMI on the following page.

MUST ALWAYS BE TESTED WITH A WOOFER OR 4 OHM RESISTIVE LOAD.

JBL part# 30706
JBL part# 30710

PB12: JBL part# 60302

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

15

PB10/12 Revision 1 Only

MODEL

Serial numbers are located on the cabinet directly below

PB10

PB12 Hum, Buzz or “Thumping”

* Revision 1 of the PB10/12: Amplifier faceplate says “Made in Canada”; Amplifier serial number starts with “AM”

See serial numbers on Page 3 for factory

Serial Number (120v)

the amplifier faceplate.

modified units

STATUS ACTION

Hum, Buzz or “Thumping”

Replace Power Amp Module S53AMI

for symptoms described in #C only

Replace Power Amp Module S64AMI

for symptoms described in #C only

Black (or silver) potted, non-serviceable S53/64AMI output module. PB10 only – No Power switch

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

16

FACTORY MODIFIED PB-10 SERIAL NUMBERS

1953 23000
7720 23896
8579 23904-23905
10145 23989
10448 23991
10458 23993
11772 23997
11792 24004
11939 24010
13128 24166
13296 24230
14371 24874-24875
14508 24888
14510 24902
14519 24905-24907
14674 24909
14822 24913-24914
15092 24919
15525 24924
15634 24926
15644-15645 24928-24929
15649 24931-24932
15654 24934
15657 24936
15659 24939
15662 24944
15673-15674 24948
15676-15677 24950
15679 24960
15681 24986
15683 24988
15692 24991
15696 24994
15702 24996
15705 24998
16413 25001
17723 25003-25005
17740 25007
18274 25015
19665 25018
20470 25020
21026 25025
21124 25029-25030
21126 25033
21637 25037
22892 25039
22894-22895 25041
22901 25043-25056
22905-22906 25058-25115
22908 25117
22913 25119-25142
22917 25144-25147
22927 25149-25152
22933 25154-25156
25158-25159 25436
25161 25691
25164 25694
25168 25698-25699
25171 25704
25174 25706
25179 25710
25185 25712-25713
25187 25715-25719
25189 25721-25730
25194 25732
25214 25734
25218-25219 25735
25229 25737-25739
25234-25236 25742-25745
25238-25243 25747-25770
25247-25249 25772-25777
25251-25252 25779-25791
25256-25257 25793-25833
25261-25263 25835-25845
25265-25267 25847-25850

25270-25272 25852-25864
25276 25866-25868
25278-25291 25870
25294-25297 25874-25881
25300 25883-25886
25302-25303 25888
25306-25307 25890-25891
25309 25893-25894
25311 25896-26000
25313-25314 26002-26012
25333-25334 26014-26076
25341 26079
25345 26081
25347-25348 26083
25351-25352 26086-26087
25358 26089-26091
25360-25361 26093-26094
25363-25364 26096-26097
2536825369 26099-26101
25371 26103-26104
25375 26106
25384-25386 26108
25391-25392 26110
25394 26112
25396 26115
25399 26118-26119
25402 26121-26124
25406 26126
25408 26128
25416 26130-26131
25419 26133-26134
25421 26136-26137
25426 26139
26141-26150 26522
26152- 26172 26525
26174 26528
26176-26185 26531
26187-26197 26533
26198-26201 26536
26203 26540-26541
26206 26543-26544
26209 26546-26554
26211 26556-26557
26213-26214 26560
26217 26565
26235 26568
26238 26573
26242 26587
26244 26599
26246 26604
26251-26252 26614-26615
26254-26255 26624-26625
26266 26627
26273 26629
26278 26632
26282 26638
26286 26641-26643
26384 26645
26388 26655
26390-26391 26658
26399-26400 26662
26402 26665
26405-26406 26669
26408-26409 26671
26411 26673
26413-26415 26675-26677
26417 26680
26419 26686
26421 26692-26694
26432 26696-26697
26438-26439 26700
26443 26702
26451-26452 26706
26457-26458 26708
26460-26462 26713-26716

26465 26718-26720
26474 26722-26725
26477 26729-26730
26479-26480 26732-26743
26483 26745-26747
26486 26750
26498 26752-26753
26503 26755
26510-26512 26757-26759
26514 26762-26768
26517 26770-26771
26520 26773-26778
26781 27376-27399
26783 27401-27503
26786 27532
26789 27553
26791 27624-27647
26793 27649-27698
26795-26797 27701-27720
26799-26801 27722-27769
26804 27771-27774
26807 27776-27852
26810 27854-27866
26813 27868-27911
26815-26816 27913-27999
26820 28001-28067
26822 28069
26825 28070
26827 28072-28073
26829 28075
26833-26834 28078
26838 28087
26840 28092-28094
26843 28096-28097
26844 28099
26846 28101-28102
26850 28105
26857 28108
26874 28110-28114
26876-26880 28116-28117
26882 28119-28120
26885-26886 28122-28123
26888-26894 28125
26913 28130-28131
26915-26917 28133
26922-26935 28137
26967 28140-28150
26984-27001 28152-28158
27010-27033 28160-28161
27100 28167
27103-27104 28172
27122-27126 28177
27142-27143 28181
27148-27149 28184
27151 28186-28187
27153 28193
27190 28196
27192 28202-28203
27196-27273 28207
27275-27277 28211
27279-27312 28215
27314-27329 28217-28218
27331-27351 28220-28221
27353-27370 28223
27372 28227
27374 28231-28234
28236-28237 29792-29860
28239-28241 29862-29915
28243 29917-30062
28245 30064-30133
28250 30152-30288
28256 30290-30345
28259 30347-30413
28264-28267 30415-30490
28270-28271 30492-30524

28283 30526-30533
28286 30535-30625
28288 30627-30649
28291 30651-30686
28293-28294 30688-30748
28296 30750-30930
28298 30932-31025
28300 31027-31072
28302-28303 31074-31123
28305-28331 31125
28333-28343 31127-31139
28345-28354 31256
28369 31771
28379-28689 35089
28691-28697 35733
28699-28708 36186
28710-28715 37400
28717-28720 39339
28722-28724 80749
28726-28731
28734
28736
28738-28740
28742-28744
28746-28750
28752-28754
28756-28821
28823-29130
29132-29142
29144-29219
29221-29276
29278-29280
29282-29327
29329-29338
29340-29379
29381-29389
29391-29451
29453-29455
29457
29459-29528
29530-29531
29533-29605
29607-29624
29626-29634
29636-29790

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

Service Bulletin

Service Bulletin JBL2001-05 Rev2 - February 2002 This is considered a Minor repair

To: All JBL Service Centers

Models: PB12 (Revision 1 only)*

Subject: Popping Every Few Seconds During Play

In the event you receive a PB12 subwoofer with the complaint: “The subwoofer “thumps” or “pops”
every few seconds of play”, follow the procedure below:

Probable Cause:

Inductor L1 (220uH) may be damaged.

Check and Replace L1 if necessary:

1) Set the unit on a padded surface and remove all external cables.

2) On the amplifier faceplate, remove the (10) Phillips mounting screws around the perimeter.

3) Remove the amplifier assembly from the enclosure. If the amp is supported correctly, no other
connectors need to be unplugged.

4) Locate Inductor L1 on the main PCB. If the windings appear charred or burnt, it must be replaced.

5) Order JBL part# 80121 and replace L1.

6) Replace the amplifier assembly back into the cabinet; replace the screws.

7) Test the unit and confirm the original problem has been corrected.

Model Serial number (120V) Status Action

PB12 * AM0035-24318 and below L1 may be damaged

if experiencing above symptoms

PB12 * AM0035-24319 and above Modified by factory None required

* Revision 1 of the PB12: Amplifier faceplate says “Made in Canada”; Amplifier serial number starts with “AM”

Black (or silver) potted, non-serviceable S64AMI output module.

17

Replace L1

with JBL part# 80121

PB12

18

Service Bulletin

Service Bulletin JBL2001-07 Rev1 - February 2002 This is considered a Minor repair

To: All JBL Service Centers

Model: PB12 (Revision 1 only)*

Subject: Possible Missing Diode D4

In the event you receive a PB12 subwoofer for any servicing reason, check for the presence of

diode D4 on the Main PCB close to the Power Amp Module (see illustration). If D4 is missing or

has been “cut out” of the circuit, it should be replaced; add JBL part# 50115. Observe polarity.

Note: The presence or absence of D4, in itself, does not contribute to, or solve, an amplifer failure.

Purpose of D4 is to reduce the possibility of an occasional Turn-OFF pop noise.

Reference for general location only; all parts or designators may not conform exactly to this drawing.

* Revision 1 of the PB12:

Amplifier faceplate says “Made in Canada”; Amplifier serial number starts with “AM”

Black (or silver) potted, non-serviceable S64AMI output module.

19

Service Bulletin

Service Bulletin JBL2003-08 – July 2003 This is considered a Minor repair

To: All JBL Service Centers

Models: PB12 (Revision 2, PCB Revision “C” or “D” only) *

Subject: Service Modification – L5 Bypass

In the event you receive a PB12 subwoofer for servicing, the following modification should be performed
to the amplifier, after identification that it is Revision 2, and with PCB Revision “C” or “D”:

1) Set the unit on a padded surface and remove all external cables.

2) On the amplifier faceplate, remove the (10) Phillips mounting screws around the perimeter.

3)

Remove the amplifier assembly from the enclosure. If the amp is supported correctly, no other connectors
need to be unplugged.

4)

Remove the plastic rear cover to access the components.

5) Locate L5 Ferrite Bead; on the opposite side of the PCB (SMD component side), solder a 16-18 gauge
jumper or buss wire across its two connections.

6) Complete any other repairs; reassemble and test the unit.

NOTE: Some woofers that were used in the PB12 had similar terminals (both .205") so there is no polarity-keying if the

woofer wires are unplugged for any reason, (even though the amp output terminals themselves are dissimilar (.205 and
.250). In this case, assure the polarity is correct if the woofer wires have been unplugged.
Green = Positiv e (.250”), Black = Negative (.205”). The “+” and “-“ markings are on the woofer terminal block. Assure the
Faston connectors are tight and crimped on the terminals.

MODEL

PB12

* Identification of the PB12 Revision 2: (120v)

1) Amplifier serial number starts with “HA”
Output transistors in the open, on a large black heatsink
Large plastic cup enclosing the rear of the amp assembly
Main PCB, bottom, solder-side contains all SMD devices
“Made in Mexico” label on outer part of cabinet

2) PCB Revision “C” and “D”
found on the long outer edge of the PCB

– Revision silkscreen can be

STATUS ACTION

All PB12 amplifiers

Revision 2 and PCB

Revision “C” and “D”

should be modified during

any service procedure to

avoid Q18,Q22 damage

Solder a jumper or buss

wire across L5 to bypass it.

TECH TIPS

20

Troubleshooting tips and solutions to common service problems

For models: PB10, PB12 (Revision 2) * TIP# JBLTT2003-04

Subject: Replacing MOSFETS Q18, Q22

In the event you need to replace MOSFET transistors Q18 or Q22 as part of a repair, it is important to use

ONLY the JBL part# FE106401110 or only the brands: International Rectifier, or Fairchild.

Replace both

Do NOT mix & match these components from different manufacturers, or batches. They should be

identical.

Q18 and Q22 MOSFET’s in the circuit, even if only one seems to be damaged.

* Late version PB10 or PB12 subwoofers (Revision 2 in the service manual) can be identified by:

• Amplifier serial number starts with “HA”

• Output transistors in the open, on a large black heatsink

• Large plastic cup enclosing the rear of the amp assembly

• Main PCB, bottom, solder-side contains all SMD devices

PB12

Exploded and Packaging Views

(IMAGE REDUCED)

1

5

9

4

2

6

7

8

3

(Rev 2 has

1 pc. Foam
per side)

10

MECHANICAL & PACKING PARTS LIST

Item # Description Qty Revision 1 Part# Revision 2 Part#

1

12" Woofer (DCR = 4.8 Ω)

2 Foot 4 203410 336486-001
3 O uter Ca rt on 1 203420 338131-001
4 Owner’s Manual 120V 1 203430 338129-001

Survey Card 1 n/a 331384-001

Warranty Card 1 n/a 331994-001
5 PB12 Amplifier Complete 1 Not For Sale Not For Sale
6 Foot Screw 4 203411 763-31110-40
7 Foam corners (Top Corners) 4 203460 n/a
8 Foam corners (Bottom Corners) 4 203470 n/a

7 & 8 Foam End Pad (Top & Bottom) 2 n/a 338132-001

9 Port tube 1 Not For Sale 336799-001

10 Logo Badge 1 336485-001 336485-001

LED Ass’y for Logo Badge 1 338125-001 338125-001

Identification Of PB12 Revisions 1 and 2 can be found on Page 2.

1 203500 338128-001

21

PB12

Amplifier Exploded View (Revision 1 Only)

00263

1

2

5

6

3

4

7

LEGEND

1 Dual RCA jack 108320
2 Power Transformer 80116
3 Level Pot 40402
4Crossover CONTROL 40707
5 Fuse Clips (2) 70323
6 2A SLO-BLO T TypeFuse (3AG)80117
7 Power Switch 70151

22

PB12

Amplifier Faceplate/Access

CROSSOVER
FREQUENCY

LEVEL

LINE LEVEL IN

PHASE

Min

Max

L

R

L R

For LFE use L or R

LFE NORMAL

PowerBass PB12

REMOVE THESE TWO SCREWS

TO REMOVE REAR COVER

AND ACCESS AMPLIFIER

LONGER SCREW HERE

PowerBass PB12

HIGH

LEVEL

IN

L

R

POWER

HIGH

LEVEL

OUT

+ –

120V
60Hz

50Hz

0º 180º

150Hz

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

ON OFF

1

2

10

5

6

4

7

8

9

3

MECHANICAL & PACKING PARTS LIST

Item # Description Qty Revision 1 Part# Revision 2 Part#

1 Level Knob 1 70313 061-020000-000
2 LFE Defeat Switch 1 70150 074-030002-000
3 PB12 faceplate 1 70325 n/a
4 HI LEVEL Input/Output Jacks 4 108116 072-060170-000
5 Phase Switch 1 70150 074-030002-000
6Crossover Frequency Knob 1 70313 061-020000-000
7 Strain Relief Plug 1 70305 061-314002-000
8 Power Cord 1 80105 083-041802-009
9 Power Switch 1 70151 074-020018-000

10 RCA Input jacks 1 108324 072-010007-000

Identification Of PB12 Revisions 1 and 2 can be found on Page 2.

23

PB12

Integrated Circuit Diagrams (Revision 1 Only)

+6V 15

16

17

V+

1 +6V

2

V+3

18

4

O/P

19 5

O/P

20

6

V- V-

21 7

22

8

SD 24

+15V 23 9 +15V

10 SD

FR 25 11 FR

I/P 26 12 I/P

GND 27 13 GND

-15V 28 14 -15V

00228

NOTE: THE FOLLOWING PROCEDURES MUST BE
FOLLOWED WHEN INSTALLING NEW S53AMI/S64AMI AMP
MODULES:

FAILURE TO FOLLOW ONE OR MORE OF THESE STEPS
MAY RESULT IN THE INSTANT DESTRUCTION OF THE
MODULE WHEN POWERED UP.

1. Align white indent marker on Amp Module with indent
marker on main PCB; alternately observe position of label
on top of the Module; incorrectly replacing the Module
180° in the PCB slot will result in its destruction.

2. All AC powered test instruments (meters, oscilloscopes,
etc.) must have a floating ground, i.e., be connected to
an isolation transformer.

3. Align and position the Amp Module before soldering.

4. Attach the Amp Module with the mounting screws before
soldering or powering up.

5. Use only rosin-core or non-acid core solder; thoroughly
de-flux the surfaces after soldering.

If the new S53AMI/S64AMI Amp Module has larger mounting
hole(s) in the case, and the stock screws no longer will fit,
and screws of the proper type cannot be obtained locally
order:

(2) part# 60301S (screws)
(2) part# 60301N (nuts)

S53AMI/S64AMI - Power Amp Module SAFETY PART

NOTE: THE PB10/12 REVISION 1 AMPLIFIER MUST ALWAYS BE TESTED

WITH A WOOFER OR 4 OHM RESISTIVE LOAD.

N-Chan JFET

LM324, TLO64, U1, U2

Q1 2N5457

D

S

G

MPSA56, Q10, Q11

2

Base

1

2

3

24

3 Collector

1 Emitter

2N4401, Q12

2

Base

1

2

3

3 Collector

1 Emitter

0227

PB12

22

Integrated Circuit Diagrams (Revision 2 Only)

25

2N5401
Q1

3 Collector

2

Base

1

2

3

1 Emitter

MPSW06RLRA,
MPSW56RLRAMPQ,
MPS2222ARLRA,
2N2907A, 2N5551,
Q2, 16, 3, 21, 19, 23, 17

3 Collector

2

Base

1

2

3

1 Emitter

OPAMP, QUAD
TL074CDR
U2, 3

BEVEL

OPAMP, DUAL
TL072CDR SO-8,
NJM4558M-TE3
U5, 6, 4

MOSFET IRF640
Q18, 22

1. G

2. D

3. S

3

12

TIP31C
Q4

MMBT3904LTI SOT23,
MMBT3906LTI SOT23,
DTC114EK SMT3,
MMBT5401 LTI,
MMBT5551 LTI
Q11, 14, 13, 5, 8, 9, 6, 10,
12, 15, 7, 20, 24, 26, 25

IR2111 HALF-BRIDGE
DRIVER
U7

BC

E

PB12

PB12 Testing Procedure (Revision 1 Only)

26

PB12

PB12 Testing Procedure (Cont.) (Revision 1 Only)

27

PB12

PB12 Testing Procedure (Cont.) (Revision 1 Only)

28

PB12

PB12 Testing Procedure (Cont.) (Revision 2 Only)

A. Power Amp Section

Resistance

Check

Resistance from S+ (SPK O/P) to GND should be >1M Ω (NO LOAD)

Resistance from V+ (C6 P+) to V- (C8 P-) gradually Fully CHARGED should read >10k Ω
Resistance from V+ (C6 P+) to S+ (SPK O/P) should read >1MΩ
Resistance from V- (C8 P-) to S+ (SPK O/P) should read >1M Ω

2. Power Up LED RED

With a 5mV signal to Low level input, LED should change to GREEN

-Voltage measurements (DVM)

OP AMP

LED

P-U4(1) P-U4(7)

RED 0Vrms 11.84VDC

GREEN 7.13Vrms -12.93VDC

3. D.C. Operation

-Voltage measurements (DVM) on CLASS D POWER AMP

Between V+ Q4(E) Q1(C)

And This

Point

Get this

Reading

GND V- GND GND GND GND GND GND GND GND

71.7V 0V -71.7V 0V -71.7V -71.5V -71.2V 0V 0V 4.65V

Q10(C)

U7(1) U7(2) U7(4) U7(6) U7(7) U7(8)

4. Check Switching Frequency

• Oscilloscope - USE THE PROBE TIP TO U6(7) TO GND

• Reading 100kHz +/-10%,24Vp-p

B. Pre Amp Section

Line Level Input Sensitivity

-Set up Turn level, X’OVER FREQ POT Fully CW and LFE switch off

Generator Set at 200mV@50Hz

Signal to Line level input

29

PB12

PB12 Testing Procedure (Cont.) (Revision 2 Only)

- Voltage measurements

OP AMP

U2(1) U2(14) U2(8) U3(7) U3(1) U3(14) U3(8) U5(7) U5(1)

306.9mV 461mV 460mV 658mV 628mV 598mV 2.326V 2.02V 3.57V 23.33V

2. High Level Input Sensitivity

-Set up Turn level, X’OVER FREQ POT Fully CW and LFE switch off

Set Generator at 1.3V@50Hz

Signal to High level input

-Voltage measurements 15.3V at speaker output

3. Low-Pass

-Set up Set Generator at 200 mV@100Hz

Signal to

Measure voltage at S+ speaker output

-Voltage measurement

X’OVER FREQ. Setting Output

CW 14.03V

CCW 4.8V

Line level input

SPEAKER

O/P

4. LFE

-Set up Set Generator at 200mV@200Hz

Signal to

Measure voltage at S+ speaker output

LFE switch Setting Output

Normal 6V

LFE 18.32V

See flow chart next page for diagnostics.

Line level input

30

PB12

PB12 Testing Procedure (Cont.) (Revision 2 Only)

,

PB12 POWER MODULE TESTING FLOW CHART

TO GROUND. ALL TEST INSTRUMENTS CONNECTED TO THE OUTPUT MUST

BE FLOATING. ATTACH THE SCOPE PROBE TIP TO S - and REFERENCE

LEAD TO S+.

(A 10mV signal may need from the input to trigger the Switch turn on)

START

Resistance check

(no load)

between V+ V-,

V+ O/P,V- O/P

and O/P to GND

is > 10K

no

no

OK

yes

yes

Power up with no

signal input

LED RED

no

no

OK

yes

yes

Check Q4(E)

TO V-

= 0V D.C.

CAUTION : SPEAKER OUTPUT IS FLOATING AND IS NOT PROTECTED AGAINST A SHORT

Check +/-15V-MOD

+/-15V voltage at

U 6(8),U6(4)

Replace

Q18,Q22

Discharge C37,

Check fuse

transformer, L4,

rectifier, C6 and C8

OK

I/P:10mv/50HZ

Check +15V/SW

Q4(E) TO V-

OK

Check

U7(1) = -58.3V

Check

FB1,FB2,C45,

C50,C60,C63,

R81,R82

Check

MUTE(-12.9V),

And

Q24,Q25,Q26

no

no

OK

yes

yes

Use scope to check

switching

frequency U6(7)

100KHz

+/-10% , ~24Vp-p

no

no

OK

yes

yes

CLASS D AMP OK

Check

MUTE(+8V) and

Q24,Q25,Q26

OK

Use scope to

check O/P U7(6)

and GND

143Vp-p square

wave shown

OK

Check

L2,L3,C71,C72,

C73

C74

Check

U7,Q16,Q17,

Q20,Q21,R87,

D26,D35,C64

31

PB12 Block Diagram Revision 2 Only

1

2

3

4

A

SPEAKER LEVEL

INPUT

PHASE CTRL
SWITCH

5

RevNo Revision note

6

7

Date Signature

8

Checked

A

Rin

Lin

B

Rout

DIF. AMP

SUMMI NG AMP

VOLUME CTRL

AMP STAGE

HPF

12dB/Octave

LPF

12dB/Octave

LPF

Variable

12dB/Octave

B

Lout

Line Level
Input

C

D

SIGNAL SENSE

SIGNAL SENEING

MUTE

ATO

* FUSE

DC OFFSET
PROTECTION

THERMAL
PROTECTION

CURRENT
PROTECTION

LINEAR
POWER SUPPLY

MUTE

CLASS D
AMPLIFIER

LIMITER /
LPF

OUTPUT-RELAY

SUMMI NG AMP

LFE

NORMAL

C

D

5.6 OHMS

EXTERNAL LED INDICATORS

E

CONTROLLED
REGULATOR

+15V SW

E

MUTE

NOTE :
120 VAC T2A-250V

F

230 VAC T1.25A-250V

1

2

3

6

7

8

F

32

PB12

PB12 Electrical Parts List (Revision 1 Only)

PB12 POWER AMP section of PCB Version 6.3 -7.0.

Part # Designator Description

50100 BR RECT RS604 6AMP Bridge rectifier
50105 D1 1N4744A 15V 1w Zener
50112 D10 1N5242B 12V .5w Zener
50104 D11 1N4148 Sig Diode
50112 D12 1N5242B 12V .5w Zener
50104 D13 1N4148 Sig Diode
50104 D14 1N4148 Sig Diode
50105 D2 1N4744A 15V 1w Zener
50114 D3 1N5265B 62V .5w Zener
50104 D4 1N4148 Sig Diode
50113 D5 1N4735A 6.2V 1W
50103 D6 1N5234B 6V .5w Zener
50104 D7 1N4148 Sig Diode
50104 D8 1N4148 Sig Diode
60157 Q1 2N5457 25V N-chnl FET
60155 Q10 2N5401 120V PNP 600mA
60155 Q11 2N5401 120V PNP 600mA
60156 Q12 2N4401 40V NPN 600mA
60102 U1 TLO64 Quad OpAmp

Capacitors

30710 C1 2200uF 100V +80 / -20 Electrolytic 105C
30718 C10 4u7F 100V BP/NP Electr DF<.1
30523 C11 330nF 100V mono ceramic
30710 C2 2200uF 100V +80 / -20 Electrolytic 105C
30532 C20 220nF 250V metallized polyester
30502 C21 100nF 50V mono ceramic
30502 C22 100nF 50V mono ceramic
30527 C24 330nF 50V mono ceramic

C25 NOT USED
30508 C26 10nF 50V mono ceramic
30513 C27 3n3F 50V mono ceramic
30502 C3 100nF 50V mono ceramic
30711 C32 22uF 35V +80/-20 Electrolytic
30715 C40 10uF 16V +80/-20 Electrolytic
30716 C41 1uF 16V +80/-20 Electrolytic
30717 C42 100uF 16V +80/-20 Electrolytic
30502 C6 100nF 50V mono ceramic
30521 C7A 100nF 250V ceramic/film
30521 C7B 100nF 250V ceramic/film

CW NOT USED
30505 CZ 100nF 100V ceramic/film

33

PB12

PB12 Electrical Parts List (Revision 1 Only)

PB12 POWER AMP section of PCB Version 6.3 -7.0.

Part # Designator Description

Resistors

R100 NOT USED
40105 R10A 0.1R .5W metal
40105 R10B 0.1R .5W metal
40105 R10C 0.1R .5W metal
40420 R11 1k .25W carbon
40420 R12 1k .25W carbon
40417 R13 47k .25W carbon
40718 R14 3k3 .25W carbon

R15 NOT USED
40735 R1A 7k5 2W metal
40735 R1B 7k5 2W metal
40735 R1C 7k5 2W metal
40405 R21 4K7 .25W carbon
40736 R22 42K2 .25W metal
40737 R23 187k .25W metal

R24 NOT USED

R25 NOT USED
40722 R26 6k8 .25W carbon
40738 R27 10k 2W metal
40739 R28 1k2 0.25W carbon
40739 R29 1k2 0.25W carbon
40735 R2A 7k5 2W metal
40735 R2B 7k5 2W metal
40735 R2C 7k5 2W metal
40703 R3 8M2 .25W carbon
40738 R30 10k 2W metal
40417 R31 47k .25W carbon
40417 R32 47k .25W carbon
40427 R33 23k7 .25W metal
40403 R34 10k .25W metal
40740 R4 33k 1W metal
40420 R40 1k .25W carbon
40701 R41 1000k .25W carbon
40741 R42 22k .5W metal
40701 R43 1000k .25W carbon
40406 R44 100k .25W carbon
40415 R45 470K .25W carbon
40701 R46 1000k .25W carbon
40409 R47 10k .25W carbon
40409 R48 10k .25W carbon
40726 R49 15k .25W carbon
40732 R5 56k2 .25W metal
40727 R50 2k2 .25W carbon
40111 R6 47R .25W carbon
40738 R7A 10k 2W metal
40738 R7B 10k 2W metal
40738 R7C 10k 2W metal
40738 R8A 10k 2W metal
40738 R8B 10k 2W metal

R9 NOT USED

34

PB12

PB12 Electrical Parts List (Revision 1 Only)

PB12 POWER AMP section of PCB Version 6.3 -7.0.

Part # Designator Description

Miscellaneous

80121 L1 220uH 5 Amp Gapped Ecore choke
80122 L2 8u5H 5 Amp ferrite bead
80122 L3 8u5H 5 Amp ferrite bead
80122 L4 8u5H 5 Amp ferrite bead
80100 CMC 2m2H 5 Amp choke
60302 MODULE S64AMI
108326 Led Harness With two LED's,Molex plug Glued into cabinet
80116 Transformer MCI4632 100VA 4632 transformer
70151 Switch SW SPST Power Switch
70322 LED socket PCB mount LED socket
80117 3AG FUSE 2A SloBlo T type
70324 0.187" PCB Tabs 7
70323 PCB Fuse Holders 2
70325 PB12 faceplate PB12 faceplate
80105 Power cord Power cord
70305 Strain relief Strain relief

PB12 PREAMP PCB Version #6.3

Part # Designator Description

Semiconductors

60102 U1 TLO 64 OP amp
60100 U2 LM324 OP amp

Capacitors Film Caps may be used in any position EXCEPT C1,C2
30707 C1 200uF 50V BP Electrolytic

30504 C10 100nF 50V mono ceramic
30504 C11 100nF 50V mono ceramic
30504 C12 100nF 50V mono ceramic
30504 C13 100nF 50V mono ceramic
30530 C16 100nF 50V mono ceramic
30531 C17 150nF 50V mono ceramic
30100 C18 330pF 50V mono ceramic
30100 C19 330pF 50V mono ceramic
30707 C2 200uF 50V BP Electrolytic
30502 C20 100nF 50V mono ceramic
30502 C21 100nF 50V mono ceramic
30502 C22 100nF 50V mono ceramic
30502 C23 100nF 50V mono ceramic
30101 C3 220pF 50V mono ceramic

C30 NOT USED
30101 C4 220pF 50V mono ceramic
30101 C5 220pF 50V mono ceramic
30101 C6 220p 50V mono ceramic

C7 0r

C8 0r
40730 C9 1k .25W Metal Resistor

35

PB12

PB12 Electrical Parts List (Revision 1 Only)

PB12 POWER AMP section of PCB Version 6.3 -7.0.

Part # Designator Description

Resistors

40405 R1 4k7 .25W carbon
40409 R10 10k .25W carbon
40731 R11 59k .25W carbon
40504 R12 45k3 .25W metal
40412 R13 33k2 .25W metal
40709 R14 68k1 .25W metal

R15 NOT USED

R16 NOT USED
40732 R17 56k2 .25W metal
40722 R18 6k8 .25W carbon
40722 R19 6k8 .25W carbon
40405 R2 4k7 .25W carbon
40722 R20 6k8 .25W carbon

R21 0r
40722 R22 6k8 .25W carbon

R23 0r
40109 R24 604r .25W metal
40412 R25 33k2 .25W metal
40405 R26 4k7 .25W metal
40109 R27 604r .25W metal
40412 R28 33k2 .25W metal
40406 R3 100k .25W carbon
40403 R30 10k .25W metal
40733 R33 12k1 .25W metal
40734 R34 120k .25W metal
40451 R35 137k .25W metal
40406 R4 100k .25W carbon
40406 R5 100k .25W carbon
40406 R6 100k .25W carbon
40717 R8 2k7 .25W carbon
40717 R9 2k7 .25W carbon

Miscellaneous

108320 RCA CONNECTOR DUAL RCA-yellow
108116 HI LEVEL I/O Binding Post OUT Binding Post
108116 HI LEVEL I/O Binding Post IN Binding Post

40402 LEVEL 5k POT Log (A) Pot
40707 Crossover CONTROL 20k POT Lin (B) Pot.

70150 LFE switch SW SPDT mini-Toggle
70150 Phase Switch SW SPDT mini-Toggle

36

PB12

PB12 Electrical Parts List (Cont.) (Revision 1 Only)

PB12 POWER AMP section of PCB Version 7.2.

Part # Designator Description

Resistors

40735 R1A 7k5 2W 5% metal SAFETY
40735 R1B 7k5 2W 5% metal SAFETY
40735 R1C 7k5 2W 5% metal SAFETY
40735 R2A 7k5 2W 5% metal SAFETY
40735 R2B 7k5 2W 5% metal SAFETY
40735 R2C 7k5 2W 5% metal SAFETY
40703 R3 8M2 .25W 5% carbon
40740 R4 33k 1W 5% metal SAFETY
40732 R5 56k2 .25W 1% metal
40111 R6 47 ohms .25W 5% carbon
40738 R7A 10k 2W 5% metal SAFETY
40738 R7B 10k 2W 5% metal SAFETY
40738 R7C 10k 2W 5% metal SAFETY
40738 R8A 10k 2W 5% metal SAFETY
40738 R8B 10k 2W 5% metal SAFETY

R9 NOT USED
40105 R10A 0.1 ohms .5W 5% metal
40105 R10B 0.1 ohms .5W 5% metal
40105 R10C 0.1 ohms .5W 5% metal
40420 R11 1k .25W 5% carbon
40420 R12 1k .25W 5% carbon
40417 R13 47k .25W 5% carbon
40718 R14 3k3 .25W 5% carbon

R15 NOT USED
40405 R21 4K7 .25W 5% carbon
40736 R22 42K2 .25W 1% metal
40737 R23 187k .25W 1% metal

R24 NOT USED

R25 NOT USED
40722 R26 6k8 .25W 5% carbon
40738 R27 10k 2W 5% metal SAFETY
40739 R28 1k2 0.25W 5% carbon
40739 R29 1k2 0.25W 5% carbon
40738 R30 10k 2W 5% metal SAFETY
40417 R31 47k .25W 5% carbon
40417 R32 47k .25W 5% carbon
40427 R33 23k7 .25W 1% metal
40403 R34 10k .25W 1% metal
40407 R35 220K .25W 5% carbon
40420 R40 1k .25W 5% carbon
40701 R41 1000k .25W 5% carbon
40741 R42 22k .5W 5% metal
40701 R43 1000k .25W 5% carbon
40406 R44 100k .25W 5% carbon
40415 R45 470K .25W 5% carbon
40701 R46 1000k .25W 5% carbon
40409 R47 10k .25W 5% carbon
40409 R48 10k .25W 5% carbon
40726 R49 15k .25W 5% carbon
40727 R50 2k2 .25W 5% carbon

37

PB12

PB12 Electrical Parts List (Cont.)

PB12 POWER AMP section of PCB Version 7.2.

Part # Designator Description

Capacitors

30710 C1 2200uF 100V +80/-20 Electrolytic 105C SAFETY
30710 C2 2200uF 100V +80/-20 Electrolytic 105C SAFETY
30502 C3 100nF 50V 20% mono ceramic
30502 6 100nF 50V 20% mono ceramic
30521 C7A 100nF 250V 20% ceramic/film SAFETY
30521 C7B 100nF 250V 20% ceramic/film SAFETY
30718 C10 4u7F 100V 20% BP/NP Electr DF<.1
30523 C11 330nF 100V 20% mono ceramic
30532 C20 220nF 250V 20% metallized polyester
30502 C21 100nF 50V 20% mono ceramic
30502 C22 100nF 50V 20% mono ceramic
30527 C24 330nF 50V 5% mono ceramic

C25 NOT USED
30508 C26 10nF 50V 10% mono ceramic
30513 C27 3n3F 50V 10% mono ceramic
30711 C32 22uF 35V +80/-20 Electrolytic
30715 C40 10uF 16V +80/-20 Electrolytic
30716 C41 1uF 16V +80/-20 Electrolytic
30717 C42 100uF 16V +80/-20 Electrolytic

CW NOT USED
30505 CZ 100nF 100V 20% ceramic/film

Semiconductors

50105 D1 1N4744A 15V 1w Zener
50105 D2 1N4744A 15V 1w Zener
50114 D3 1N5265B 62V .5w Zener
50115 D4 1N4938 5% Sig Diode

EDN 10025 changes D4 on poweramp section from 1N4148 to 1N4938 part # 50115 June 26
50113 D5 1N4735A 6.2V 1W
50103 D6 1N5234B 6V .5w Zener
50104 D7 1N4148 5% Sig Diode
50104 D8 1N4148 5% Sig Diode
50112 D10 1N5242B 12V 5% .5w Zener
50104 D11 1N4148 Sig Diode
50112 D12 1N5242B 12V .5w Zener
50104 D13 1N4148 Sig Diode
50104 D14 1N4148 Sig Diode
60157 Q1 2N5457 25V N-chnl FET
60155 Q10 2N5401 120V PNP 600mA
60155 Q11 2N5401 120V PNP 600mA
60156 Q12 2N4401 40V NPN 600mA
50100 DIODE BRIDGE RS604 6AMP Bridge rectifier SAFETY
60102 U1 TLO64 Quad OpAmp
60302 MODULE S64AMI Power Amp Module SAFETY

Miscellaneous

80121 L1 220uH 5 Amp 5% Gapped Ecore choke
80122 L2 8u5H 5 Amp 5% ferrite bead

38

PB12

PB12 Electrical Parts List (Cont.)

PB12 PREAMP section of PCB Version 7.2.

Part # Designator Description

80122 L3 8u5H 5 Amp 5% ferrite bead
80122 L4 8u5H 5 Amp 5% ferrite bead
80138 CMC 3m6H 5 Amp choke SAFETY
70322 LED 3 Molex 2 header Male connector
108326 LED Harness Molex 2 socket Glued into cabinet With 2 Bi-color LED
70323 3AG TYPE 3AG PC CLIP 2 PCB-mount fuse clips SAFETY
80117 3AG FUSE 2A fuse SloBlo, 3AG SAFETY
70324 0.187" Tabs 6 0.187" PCB fastons
70328 0.250" Tabs 1 0.250" PCB fastons
70325 PB12 faceplate PB12 faceplate
80105 Power cord Power cord SAFETY
70305 Strain relief Strain relief SAFETY
70151 Switch SW SPST Power Switch SAFETY
80116 Transformer MCI4632 100VA 4632 transformer SAFETY

PREAMP section of PCB Version 7.2

Resistors

40405 R1 4k7 .25W 5% carbon
40405 R2 4k7 .25W 5% carbon
40406 R3 100k .25W 5% carbon
40406 R4 100k .25W 5% carbon
40406 R5 100k .25W 5% carbon
40406 R6 100k .25W 5% carbon
40717 R8 2k7 .25W 5% carbon
40717 R9 2k7 .25W 5% carbon
40409 R10 10k .25W 5% carbon
40731 R11 59k .25W 5% carbon
40504 R12 45k3 .25W 1% metal
40412 R13 33k2 .25W 1% metal
40709 R14 68k1 .25W 1% metal

R15 NOT USED

R16 NOT USED
40732 R17 56k2 .25W 1% metal
40722 R18 6k8 .25W 5% carbon
40722 R19 6k8 .25W 5% carbon
40722 R20 6k8 .25W 5% carbon

R21 0 ohms
40722 R22 6k8 .25W 5% carbon

R23 0 ohms
40109 R24 604 ohms .25W 1% metal
40412 R25 33k2 .25W 1% metal
40405 R26 4k7 .25W 1% metal
40109 R27 604 ohms .25W 1% metal
40412 R28 33k2 .25W 1% metal
40403 R30 10k .25W 1% metal
40733 R33 12k1 .25W 1% metal
40734 R34 120k .25W 1% metal
40451 R35 137k .25W 1% metal
40402 LEVEL 5k POT 20% Log (A) Pot
40707 LOPASS Dual 20k POT 20% Lin (B) Pot.

39

PB12

PB12 Electrical Parts List (Cont.)

PB12 PREAMP section of PCB Version 7.2.

Part # Designator Description

Capacitors Film Caps may be used in any position EXCEPT C1, C2
30707 C1 200uF 50V 20% BP Electrolytic

30707 C2 200uF 50V 20% BP Electrolytic
30101 C3 220pF 50V 20% mono ceramic
30101 C4 220pF 50V 20% mono ceramic
30101 C5 220pF 50V 20% mono ceramic
30101 C6 220p 50V 20% mono ceramic

C7 0r

C8 0r
40730 C9 1k .25W 1% Metal Resistor
30504 C10 100nF 50V 10% mono ceramic
30504 C11 100nF 50V 10% mono ceramic
30504 C12 100nF 50V 10% mono ceramic
30504 C13 100nF 50V 10% mono ceramic
30530 C16 100nF 50V 5% mono ceramic
30531 C17 150nF 50V 5% mono ceramic
30100 C18 330pF 50V 20% mono ceramic
30100 C19 330pF 50V 20% mono ceramic
30502 C20 100nF 50V 20% mono ceramic
30502 C21 100nF 50V 20% mono ceramic
30502 C22 100nF 50V 20% mono ceramic
30502 C23 100nF 50V 20% mono ceramic

C30 NOT USED

Semiconductors

50104 D50 1N4148 5% Sig Diode
50104 D51 1N4148 5% Sig Diode
50104 D52 1N4148 5% Sig Diode
50104 D53 1N4148 5% Sig Diode
50104 D54 1N4148 5% Sig Diode
50104 D55 1N4148 5% Sig Diode
60102 U1 TLO 64 Quad OP-AMP
60100 U2 LM324 Quad OP-AMP

Miscellaneous (See pages 15-17 for more external parts)

70150 LP DEFEAT SW SW SPDT mini-Toggle
70150 PHASE SWITCH SW SPDT mini-Toggle
108324 Li, Ri RCA connector 90 Deg DUAL RCA-yellow
108116 HI LEVEL I/O Binding Post OUT Binding Post
108116 HI LEVEL I/O Binding Post IN Binding Post

40

PB12

PB12 Electrical Parts List (Cont.)

Revision 2 Only

Part Number Description Qty Reference designators

Resistors

020-220497-120 Film Resistor 2K2 1/4W J 1 R11
021-100401-120 MOF Resistor 1K 1W J 1 R103
021-120403-020 MOF Resistor 1K2 3WS J 1 R9
021-120405-020 MOF Resistor 1K2 5WS J 1 R6
022-500003-020 KNP Resistor 0 ohms05 3WS J 1 R104
024-000098-120 SMD Resistor 0 ohms 1/8W J 2 R125, 126
024-100298-120 SMD Resistor 10 ohms 1/8W J 2 R81, 82
024-100398-120 SMD Resistor 100 ohms 1/8W J 1 R62
024-100498-120 SMD Resistor 1K 1/8W J 10 R79, 83, 92, 95, 96, 105,

108, 127, 65

024-100598-120 SMD Resistor 10K 1/8W J 30 R2, 17, 19, 20, 21, 37, 54, 58,

63, 69, 71, 72, 74, 75, 84, 88,
89, 97, 106, 109, 111, 113-117,

119, 120, 123, 124
024-100698-120 SMD Resistor 100K 1/8W J 6 R3, 22-25, 112
024-110598-100 SMD Resistor 11K 1/8W F 1 R98
024-120698-120 SMD Resistor 120K 1/8W J 1 R39
024-121598-100 SMD Resistor 12K1 1/8W F 1 R38
024-137698-100 SMD Resistor 137K 1/8W F 1 R32
024-150498-120 SMD Resistor 1K5 1/8W J 2 R67, 68
024-180598-120 SMD Resistor 18K 1/8W J 1 R29
024-187698-100 SMD Resistor 187K 1/8W F 1 R45
024-200598-120 SMD Resistor 20K 1/8W J 1 R94
024-220398-120 SMD Resistor 220 ohms 1/8W J 1 R90
024-220498-121 SMD Resistor 2K2 1/8W J 3 R1, 87, 61
024-220598-120 SMD Resistor 22K 1/8W J 1 R118
024-220798-120 SMD Resistor 2M2 1/8W J 2 R80, 121
024-237598-120 SMD Resistor 23K7 1/8W F 1 R48
024-243698-100 SMD Resistor 243K 1/8W F 1 R36
024-270498-120 SMD Resistor 2K7 1/8W J 2 R73, 64
024-300398-120 SMD Resistor 300 ohms 1/8W J 1 R55
024-300598-120 SMD Resistor 30K 1/8W J 1 R56
024-330498-120 SMD Resistor 3K3 1/8W J 9 R7, 8, 26, 27, 12-15, 59
024-330598-120 SMD Resistor 33K 1/8W J 2 R4, 5
024-360498-120 SMD Resistor 3K6 1/8W J 1 R28
024-390498-120 SMD Resistor 3K9 1/8W J 1 R93
024-390598-120 SMD Resistor 39K 1/8W J 1 R77
024-430498-100 SMD Resistor 4K3 1/8W F 1 R78
024-453598-100 SMD Resistor 45K3 1/8W F 1 R30
024-470298-120 SMD Resistor 47 ohms 1/8W J 2 R101, 102
024-470398-120 SMD Resistor 470 ohms 1/8W J 3 R76, 99, 100
024-470498-120 SMD Resistor 4K7 1/8W J 2 R85, 86
024-470598-120 SMD Resistor 47K 1/8W J 4 R44, 47, 49, 107
024-470698-120 SMD Resistor 470K 1/8W J 1 R70
024-470798-120 SMD Resistor 4.7M 1/8W J 1 R60
024-487498-100 SMD Resistor 4K87 1/8W F 2 R51, 53
024-510398-120 SMD Resistor 510 ohms 1/8W J 1 R57
024-560598-120 SMD Resistor 56K 1/8W J 1 R122
024-620398-100 SMD Resistor 620 ohms 1/8W F 2 R16, 18
024-680498-120 SMD Resistor 6.8K 1/8W J 6 R46, 91, 40, 41, 43, 42
024-680598-120 SMD Resistor 68K 1/8W J 6 R33, 34, 31, 50, 52, 66
024-820598-120 SMD Resistor 82K 1/8W J 1 R69
026-200595-269 VR2 FREQUENCY POT PN:RD163121R034-20KBx2(EJ) 1 VR2
026-500495-252 VR1 LEVEL POT P/N:RK163111R522-5KA (EJ) 1 VR1

41

PB12

PB12 Electrical Parts List (Cont.)

Revision 2 Only

Part Number Description Qty Reference designators

Capacitors

031-100244-100 SMD Ceramic Capacitor 0u01/50V K 7 C33, 45, 51, 66, 67, 5, 10
031-100343-100 SMD Capacitor 100pF/50V J 3 C16, 36, 58
031-100344-100 SMD Capacitor 0u1/50V K 16 C11, 42-44, 46-49, 52, 54, 55,

60, 63, 71, 74, 77
031-100364-100 SMD Capacitor 0.1uF/100V K 2 C3, 7
031-220344-100 SMD Capacitor 220pF/50V J 5 C14, 15, 20, 21, 19
031-330444-300 SMD Capacitor 3300pF/50V K 2 C40, 34
031-470244-102 SMD Capacitor 0u047/50V K 2 C62, 59
031-560243-100 SMD Capacitor 56pF/50V J 2 C57, 61
031-560343-102 SMD Capacitor 560pF/50V J 1 C56
032-100484-200 END PE Capacitor 1uF/250V K 2 C70, C70B
033-200645-300 NP Capacitor 200u/50V M 2 C17, 18
033-470444-270 NPE 4u7/50V K 1 C73
033-680464-270 NPE 6u8/100V K 1 C72
034-100525-300 Electrolytic Capacitor 10uF/25V M 1 C35
034-100625-300 Electrolytic Capacitor 100uF/25V M 1 C64
034-220525-301 Electrolytic Capacitor 22uF/25V M 6 C4, 9, 41, 39, 50, 53
034-220615-301 Electrolytic Capacitor 220uF/16V M 1 C37
034-330525-300 Electrolytic Capacitor 33uF/25V M 1 C1
034-330615-300 Electrolytic Capacitor 330uF/16V M 2 C12, 78
034-330780-300 Electrolytic Capacitor 3300uF/80V M 2 C6, 8
034-470415-301 Electrolytic Capacitor 4u7/50V M 1 C2
034-470615-301 Electrolytic Capacitor 470uF/16V M 1 C65
038-100363-300 MPE Capacitor 0u1/100V J 7 C68, 69, 26, 27, 28, 29, 30
038-150393-300 MPE Capacitor 0u15/63V J 1 C25
038-330393-300 MPE Capacitor 0u33/63V J 1 C31
039-100390-100 UL Capacitor 0u1/275V 1 CXAC1

Semiconductors

051-000600-100 NPN Transistor MPSW06RLRA 2 Q2, Q16
051-005600-100 NPN Transistor MPSW56RLRA MPQ TO-92 1 Q3
051-222200-100 NPN Transistor PN:MPS2222ARLRA TO-92 1 Q21
051-290700-100 NPN Transistor P2N2907A TO-92 2 Q19, 23
051-540101-000 PNP Transistor 2N5401 TO-92 1 Q1
051-555100-000 NPN Transistor 2N5551 TO-92 1 Q17
052-400080-000 Bridge rectifier PN:RS804 400V, 8A 1 BR1
053-211100-000 IC;Half-Bridge Driver PN:IR2111 1 U7
054-000100-100 SMD Diode ES1D 200V, 1A, 35ns 5 D5, 26, 29, 33, 38
054-001001-100 SMD Zener Diode 10V SOT-23 DZ23C10 1 D35
054-001500-100 SMD Zener Diode 15V SOT-23 DZ23C15 3 D6, 7, 9
054-007200-100 SMD IC Dual Op-Amp TL072CDR SO-8 (TI) 2 U5, 6
054-007400-100 SMD IC Quad Op-Amp PN:TL074CDR (TI) 2 U2, 3
054-033904-100 SMD TR NPN (MOTOROLA) MMBT3904LT1 SOT23 6 Q11, 14, 13, 5, 8, 9
054-033906-100 SMD TR PNP (MOTOROLA) MMBT3906LT1 SOT23 4 Q6, 10, 12, 15
054-045580-100 SMD Dual Op-Amp NJM4558M-TE3 DMP-8 1 U4
054-050600-100 SMD Zener Diode 5.6V SOT-23 DZ23C5V6 3 D24, 36, 37
054-211400-100 SMD NPN Transistor DTC114EK SMT3 1 Q7
054-414803-100 SMD Zener Diode LL4148 26 D1-4, 8, 10-23, 27, 28, 30-32,

34, 39
054-540100-100 SMD PNP Transistor MMBT5401 LT1 3 Q20, 24, 26
054-555100-100 SMD NPN Transistor MMBT5551 LT1 1 Q25
051-003100-000 NPN Transistor TIP31C TO-220 1 Q4
FE1064011100 MOSFET IRF640 TO-220 2 Q18, 22

42

PB12

PB12 Electrical Parts List (Cont.)

Revision 2 Only

Part Number Description Qty Reference designators

Miscellaneous

041-115001-000 Bead Coil YT-10911 1 L5
043-300101-000 Inductor 30uH YT-10033 1 L2
043-324300-000 Inductor 324uH YT-10778 1
043-560200-000 Inductor 56uH YT-10779 1
043-700101-000 Toroidal Inductor 70uH YT-10682 1 L3
044-100100-000 SMD Ferrite Bead 600R/100MHz 1206 2 FB1, FB2
072-010007-000 RCA Housing SCJ-1020 2P(G) WHT, RED 1 CONN1
072-040039-000 Terminal PC205 (t=0.8m/m) T205MA 1 S­072-040064-000 Terminal PC250(t=0.8), T250MA 1 S+
072-040096-000 Terminal (t=0.8mm) PC187(0.8) 7 AC1, AC3, T1, T2, AC2,

SW2, SW4
072-040169-000 Connector 2 PIN JS-1001-2 P:2.5mm 1 CONN3A
072-060170-000 Binding Posts HI LEVEL Input/Output Jacks 4 BP/IP, BP/OP
093-105202-300 Fuse UL GSL(2AG) 250V, 5*20mm 1
073-050001-000 FUSE CLIP P/N:CFFH1206 2
074-030002-000 Toggle SW P/N L101 2 SW5, SW6
074-300018-000 Relay PN:943-1C-48D 1 K1
042-010053-003 Power Transformer YT-10616-4 1
061-020000-000 Level-Volume Knob 20 x 15 m/m UL 94V-0 Blk 2
061-314002-000 Strain relief SB4F-2 2
063-010012-000 Clamps for output transistorsTRK-1 4
063-531808-000 Rear plastic cover w/G ABS 1
073-032315-601 Heatsink 70 x 58 x 20 mm 1
074-020018-000 Main Power switch RF1003-BB4-0 1
083-041802-009 Power Cord 120V SPT-2 BLK #18 T187 1
181-911600-161 Output wires #16 AWG UL1007 Blk 1
181-911655-135 Output wires #16 AWG UL1007 Green 1
181-921600-000 Output wires #16 AWG UL1015 Blk 1
181-921699-000 Output wires #16 AWG UL1015 Wht 1

43

PB12 (PCB version 6.3) (Revision 1 Only)

44

PB12 (PCB version 6.3) (Cont.) (Revision 1 Only)

45

PB12 (PCB version 6.3) (Cont.) (Revision 1 Only)

46

47

PB12 (PCB version 6.4) Power Amp Only (Revision 1 Only)

PB12 (PCB version 7.2) (Revision 1 Only)

48

PB12 (PCB version 7.2) (Revision 1 Only)

49

PB12 (PCB version 7.2) (Revision 1 Only)

50

51

52

PB12 Revision 1 Schematic Diagrams POWER AMP (PCB version 7.0)

151413121110987654321

I

R46

1000k

SIGNAL LED & AUTO MUTE

R50

2k2

C6

100nF

R1A
7k5

R9

NOT USED

1N4148

D14

D12
1N5242B

D6

1N5234B

1N4735A

R1B
7k5

C21

100nF

100nF

D11

R6
47R

1N5265B

D4

D2

1N4744A

R43

1000k

D1

D3

R3

8M2

1N4744A

1N4148

1N5242B

D10

S64

+6V

V+

O/P

V-

+15V

S/D

FR

I/P

GND

-15V

MODULE

C42

100uF

D5

UVLO

R1C
7k5

R4
33k

1N4938

C22

D7

D8

1N4148

1N4148

R add

C32
22uF

TLO64

C41

4

3

1

U1

2

11

1uF

R41

1000k

R7C

R7B

R7A

10k

10k

10k

R27

10k
R28
1k2

R29
1k2

R30

10k

220k

R100

6
5
4
3
2
1

To U1 Pin 4

C25

R23

187k

12

13

-15

NOT USED

4

U1

TLO64

11

NOT USED

14

R24

NOT USED

C26
10nF

To U1 Pin 11

+15

C24

330nF

R21
4K7

CONNECTOR

AV SW

NOT USED

R32

47k

10

R33

9

23k7

C40

R40

1k

10uF

1

R26

2

6k8

3

R31

47k

4

R34

8

U1

10k

TLO64

C27

11

3n3F

H

G

F

E

D

C

Un-designated Connector

+15V

mute
GND
GND

SIG

-15V

To/From PREAMP

NOT USED

R22

42K2

R25

NOT USED

R45

470K

4

5

7

U1

6

TLO64

11

R47

C3

100nF

10k

Q1

2N5457

L2

8u5H

To AC Feed

To GND

To AC Return

R42

R44
100k

22k

C20

220nF

R5
56k2

D13

1N4148

Not Connected

R49
4k7

V+ LED

2
3

MOLEX 2

R48
4k7

R48 & R49 changed to 4k7

SHORT CIRCUIT PROTECT

Q11

R12

2N5401

1k

Q10

2N5401

R10A

0.1R

4u7F

L1

220uH

R11

1k

R10C

R10B

0.1R

0.1R

MCI 4632

TRX

C11

330nF

R15

NOT USED

TRANS. PRI.

QUICK FIT TERMINAL

C10

TRANSFORMER IS MOUNTED ON FACEPLATE

R13

47k

LED Harness

2
3

MOLEX 2

Q12

2N4401

L4

8u5H

L3

8u5H

3AG FUSE
2A SloBlo

LED1/2 Preamp

LED1/2 Preamp

On Harness

2 Clr LED

R14

3k3

LIVE

QUICK FIT TERMINAL

CZ

100nF

CW

NOT USED

On Faceplate

SW SPST

On Harness

2 Clr LED

SPK 1

QUICK FIT TERMINAL

SPK 2

QUICK FIT TERMINAL

To Power Cord

To Power Cord

I

H

G

F

E

D

C

AC Feed

C7A

V+

R2C

R2B
7k5

BR RECT

7k5

RS604

C2
2200uF

R2A
7k5

B

R8A
10k

A

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

C1

2200uF

R8B

10k

CMC

V-

2m2H

100nF

C7B

100nF

QUICK FIT TERMINAL

GND

QUICK FIT TERMINAL

AC Return

QUICK FIT TERMINAL

Part No:

Date:

Drawn:

Rev.

Version 7.0 (PWRAMP)

14-Feb-2001

MS/LL

Sheet:

1

2of2

53

B

A

PB12 Revision 1 Schematic Diagrams PREAMP (PCB version 7.2)

151413121110987654321

I

3rd Order Hi-Pass

NOT USED

C8

0r

R15

NOT USED

13

U1

12

C11

100nF

R16

2

C9

3

1k

14

R20

6k8

To Pin 11 U1/U2

To Pin 4 U1/U2

R17

56k2

+15V

-15V

TLO64

17

CONN 1

6
5
4
3
2
1

NOT USED

+15V

mute

GND
GND
SIG

-15V

To/From PWRAMP

DUAL RCA

B-POST HiLev I/O

R

L

OUT

From PwrAmp

From PwrAmp

R In

GND

L In

RCA CONNECTOR

C1

200uF

R

L

C2

200uF

H

G

F

E

D

C

B

R27

150nF

14

C17

5k POT

1

LEVEL

2

2

3

2nd Order Hi-Pass

R33

12k1

C16

100nF

R34

120k

LoPass Defeat Sw.

SW SPDT

1

3

NOT USED

SW SPDT

Phase Switch

2

3

100nF

2

J1

R12

1

45k3

3

R13

33k2

-15V
1

U2

LM324

+15V

C23

R26

4k7

604r

R28

C18

330pF

C19

330pF

R24

604r

R1

4k7

R2

IN

4k7

LED 2

1
2

NOT USED

LED1

NOT USED

33k2

R25

33k2

C3

220pF

R6

R5

R4

R3

100k

1
2

D51

C4

R8

2k7

1N4148

220pF

6

5

1N4148

D53

U1

1N4148

D52

R11

59k

7

1N4148

C6

220p

R10

10k

D54

+15V

10

8

U1

9

-15V

R9

2k7

C5

220pF

2nd Order LO-PASS

7

0r

R21

8

NOT USED

9

LO PASS CONTROL 3

NOT USED

LO PASS CONTROL 4

100nF

R22

6k8

10

11

R23

0r

12

1N4148

D50

C21

100nF

C12

REMOTE

NOT USED

1N4148

D55

100nF

13

12

C13

100nF

3
2
1

C20

U2

R14

68k1

6

U2 U1

5

R35

137k

LO PASS CONTROL 1

R18

1

6k8

R19

6k8

C22

LO PASS CONTROL 2

100nF

2nd Order LO-PASS

20k POT

3

2

20k POT

456

C7

0r

C10

100nF

GAIN STAGE

C30

NOT USED

9

U2

10

R30

10k

8

I

H

G

F

E

D

C

B

Part No:

Revision 7.2 (PREAMP)

Date:

25-Oct-2001

Drawn:

A

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Rev.

MS/LL

1

Sheet:

1of2

54

A

PB12 Revision 1 Schematic Diagrams POWER AMP (PCB version 7.2)

151413121110987654321

I

R46

1000k

SIGNAL LED & AUTO MUTE

R50

2k2

C6

100nF

R1A
7k5

R9

NOT USED

1N4148

D14

D12
1N5242B

D6

1N5234B

1N4735A

R1B
7k5

C21

100nF

100nF

D11

R6
47R

1N5265B

D4

D2

1N4744A

R43

1000k

D1

D3

R3

8M2

1N4744A

1N4148

1N5242B

D10

S64

+6V

V+

O/P

V-

+15V

S/D

FR

I/P

GND

-15V

MODULE

C42

100uF

D5

UVLO

R1C
7k5

R4
33k

1N4938

C22

H

G

F

NOT USED

E

D

C

*ALL SAFETY PRECAUTIONS IN THIS MANUAL SHOULD BE

CONN 2

+15V

mute
GND
GND

SIG

-15V

NOT USED

To/From PREAMP

R22

42K2

R25

6
5
4
3
2
1

To U1 Pin 4

C25

R23

187k

12

13

NOT USED

4

U1

TLO64

11

-15

14

NOT USED

To U1 Pin 11

C24

330nF

R21
4K7

CONNECTOR

R24

R32

47k

R33

23k7

C26
10nF

+15

AV SW

1
2
3

NOT USED

10

9

U1

4

11

C40

10uF

R31

47k

8

TLO64

TLO64

C41

4

3

1

U1

2

11

1000k

R7A

10k

1uF

R41

R7B

R7C

10k

10k

R27

10k

R30

10k

R40

1k

R26

1N4148

D7

6k8

R28
1k2

R29
1k2

D8

1N4148

R35

C32
22uF

220k

R34

10k

C27

3n3F

FOLLOWED DURING SERVICING. COMPONENTS IDENTIFIED

WITH THE IEC SYMBOL

DESIGNATED COMPONENTS IN WHICH SAFTETY CAN BE OF

SPECIAL SIGNIFICANCE WHEN REPLACING A COMPONENT

IDENTIFIED WITH

B

A

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

!

IN THE SCHEMATIC DIAGRAM ARE

!

.

DIODE BRIDGE

R2A

R2B
7k5

C2
2200uF

7k5

C1

2200uF

R8B

R8A

10k

10k

V+

R2C
7k5

RS604

R45

470K

4

5

7

U1

6

TLO64

11

R42

R44
100k

22k

C20

220nF

L2

8u5H

C3

100nF

R5
56k2

CMC

V-

3m6H

R47
10k

Q1

2N5457

!

CX

To AC

To GND

To AC

30535

Not Used

L1

1N4148

4u7F

220uH

D13

2N5401

R10A

0.1R

Not Used

L5

L6

Not Used

R49

R48
4k7

4k7

SHORT CIRCUIT PROTECT

R12

1k

Q10

R11

1k

R10B

R10C

0.1R

0.1R

30521

C7A
100nF

C7B
100nF

30521

C11

R15

NOT USED

!

TRX

MCI 4632

Part No:

Date:

Drawn:

Rev.

80116

C10

!

!

Q11

2N5401

330nF

TO TRANS. PRI.

QUICK FIT TERMINAL

TRANSFORMER IS MOUNTED ON FACEPLATE

AC

QUICK FIT TERMINAL

GND

QUICK FIT TERMINAL

AC

QUICK FIT TERMINAL

Revision 7.2 (PWRAMP)

25-Oct-2001

MS/LL

1

LED Harness

LED 3

1
2

Molex 2

Molex 2

Header Socket

R13

47k

Q12

2N4401

Sheet:

LED1/2 Preamp

LED1/2 Preamp

1
2

R14

3k3

L4

8u5H

L3

8u5H

80117

!

3AG FUSE

2A SloBlo

2of2

On Harness

On Harness

Bi-Clr LED

Bi-Clr LED

SPK 1

CZ

QUICK FIT TERMINAL

100nF

SPK 2

CW

QUICK FIT TERMINAL

NOT USED

On Faceplate

LIVE

QUICK FIT TERMINAL

SW SPST

!

70151

80105

!

Power Cord

I

H

G

F

E

D

C

B

A

55

PB12 Revision 2 Schematic Diagrams PREAMP

NOTE: THIS VOLTAGE IS 

REFERENCED TO -V, NOT 

CIRCUIT GROUND

56

PB12 Revision 2 Schematic Diagrams POWER AMP

NOTE: THIS VOLTAGE IS REFERENCED 

TO -V, NOT CIRCUIT GROUND

NOTE: THIS VOLTAGE IS REFERENCED 

TO -V, NOT CIRCUIT GROUND

57