POWER AMPLIFIER
KAC-929
SERVICE MANUAL
© 2001-3 PRINTED IN KOREA
B51-7768-00 (K) 3380
POWER AMPLIFIER
LEFT
BRIDGED
SPEAKER
OUTPUT
RIGHT
POWER IN
P.CON
BATT.
GND
30
30
FUSE(30Ax2)
KAC-929
STEREO/BRIDGEABLE
AMPLIFIER
MAXIMUM POWER
SCREW SET
(N99-1587-05)
ACCESSORY
(W01-1516-05)
CONNECTING CORD ASSY
(E30-4950-05)
KAC-929
2
BLOCK
DIAGRAM
ISOLATION
AMPLIFIER
L
ISOLATION
AMPLIFIER
R
B.BOOST
EXPANDER
INVERTER
SW3
SW4
SW1
(L)
INPUT SENS.
MIXER
LOW
PASS
SW2
IC1
IC2
IC3
IC3
IC4
BUFFER
IC3
MUTE
Q3
STAGE
DIFFERENTIAL
107,109,111
Q101,103,105,
B-CLASS
121,123,125,127
Q113,115,117,119,
STAGE
OFF/+6/+12
BASS BOOST
OPERATION
ST/MONO
LPF
ON/OFF
EXP.
ON/OFF
INPUT SENS.
(R)
B.BOOST
IC2
SW3
EXPANDER
INVERTER
SW4
BUFFER
IC3
MUTE
Q4
Q114,116,118,120,
STAGE
Q102,104,106,
108,110,112
DIFFERENTIAL
STAGE
122,124,126,128
B-CLASS
OUTPUT
SPK.
SPK.
OUTPUT
V
SPK
L
SPK
R
DC DETECTOR
OVER LOAD DETECTOR
DC/DC
CONVERTER
CIRCUIT
OVER VOLTAGE
PROTECTION
THERMAL
AVR
Q1,2
Q11-22
IC5
Q5-8,29-33
Q24
P.CON
CIRCUIT
Q23,25-28
P.C.
BATTERY
V
IC1
KAC-929
3
CIRCUIT DESCRIPTION
-20
-20
-10
0
+10
-10
0
+10
(dB)
(dB)
OUTPUT
LEVEL
INPUT LEVEL
Fig.1
(A)
(B)
(C)
-20
-20
1.1dB
2.1dB
3.2dB
5.3dB
6.5dB
0.7dB
0.15W
-30
-30
-10
-5
-7
-15
-25
0
0
150W
15W
1.5W
-10
(dB)
(dB)
OUTPUT
LEVEL
INPUT LEVEL
Fig.2
200mV
63mV
20mV
6.3mV
(4
)
0dB=24.5V
(4
150W)
R2 20K
GAIN
VARIABLE
R1 10K
RECTIFIER
R3
20K
R4
30K
THD TRIM
R3
INVERTER IN
RECT CAP
VREF
OUTPUT
1.8V
RECT IN
G IN
Fig.3
[Expander Circuit]
The expander circuit has been designed to expand
the range of audio.
Specifically, it inputs a signal with variation over 10
dB and outputs a signal with variation over 20 dB.
In other words, the expander circuit can make loud
sound louder and small sound smaller.
Its characteristic is as shown in Figure 1, which
shows its characteristic (B) in comparison with the
characteristic of an ordinary amp (A).
(A) Characteristic of ordinary amp
(B) Characteristic of expander
(C) Characteristic of expander amp used in the set
The point in incorporating an expander circuit in this
set is to make the audio more powerful, with punch in
it.
The expander amp used in the set outputs similar
audio to ordinary amp when the input level is low,
while it can provide powerful audio with punch when
the input level is above a certain level.
Figure 2 shows the characteristics of the expander
amp used in this set.
It shows that the effect described above is applied in
the same way all over the bandwidth
Appendix
IC4 block diagram is as shown in Figure 3.
KAC-929
4
ADJUSTMENT
No.
ITEM
INPUT
SETTINGS
OUTPUT
SETTINGS
RECEIVER
SETTINGS
ALIGNMENT
POINTS
ALIGN
FOR
FIG.
Connect a cassette receiver or CD receiver.
1
IDEL CURRENT
-
Connect a DC
voltmeter
between CN2
(L/R) and J2
(SP.OUT, L+/R-)
VOLUME : 0
VR3 (L ch)
VR4 (R ch)
(X09-)
2.5mV
(a)
DC Voltmeter
(a)2.5mV
DC Voltmeter
(a)2.5mV
VR4(Rch)
VR3(Lch)
CN2
Lch
Rch
SP. OUT
L
R
ACE
G
I
BD
F
H
J
2
1
3
5
7
4
6
R20
R22
R43
R28
R27
R21
R4
R19
R3
R5
R6
R7
R67
R61
R49
R46
R68
R54
R59
R52
R50
R45
R33
R34
R35
R44
R31
R32
R36
R40
R41
R42
R37
R38
R39
C1
C24
C41
C42
C23
C2
R8
C6
C5
C16
C15
C35
C36
C17
C18
R63
R57
R51
R55
R53
R47
R64
R62
R58
R60
R48
R65
R56
R69
R70
R66
C20
C19
C233
1
7
8
14
7
1
14
8
8
14
1
7
1
8
9
16
IC3
IC2
IC1
D24
IC5
ST
MONO
LPF
OFF
ON
OFF
ON
EXP
ANDOR
OFF
6dB
12dB
BASS
BOOST
D102
D25
D27
D26
CN1
CN4
CN3
J1
J2
Q7
Q119
Q115
Q5
Q109
Q
111
Q117
Q113
J3
Q8
Q118
D15
D7
D4
D3
D1
D2
Q103
Q101
Q3
CN3
CN4
S1
S3
S4
D49
D52
Q114
D50
D47
D48
D45
CN2
Q2
D23
Q1
D42
S2
D55
Q127
Q123
WH1
Q121
Q125
Q122
Q126
Q124
Q128
Q13
Q15
Q12
Q18
Q14
D41
Q11
D43
Q108
Q107
IC4
E2
D13
D11
Q105
D101
Q6
D19
D17
D28
D44
Q110
Q112
D5
D6
Q16
Q17
E1
Q120
Q116
D16
D8
Q104
Q102
Q4
D9
D14
D12
Q106
D20
D18
D10
Q25
Q26
Q24
D21
D22
Q19
Q21
Q20
Q22
D40
D31
Q28
Q27
Q33
Q30
D36
Q32
D35
Q29
Q31
D33
D34
D30
D37
D38
D32
Q23
E4
D46
D51
D100
E3
(J74-1195-11)
X09-5380-10 A/2
X09 B/2
R244
R245
R249
R248
R250
R247
R246
R278
R275
L5
W226
W82
W202
W203
W223
W224
W282
W97
W307
W293
W95
W109
W98
W124
W88
W208
W94
W104
W118
W135
W92
W110
W123
W117
W150
W79
W39
W30
W46
W29
W47
W36
W52
W13
W85
W100
W275
W225
W277
W54
W41
W21
W42
W4
W40
W48
W12
W50
W31
W51
W38
W56
W49
W18
W59
W6
W14
W33
W19
W23
W25
W70
W37
W15
W32
W28
W2
W22
W16
W83
W101
W76
W89
W80
W72
W91
W253
W288
W242
W230
W231
W262
W263
W287
W180
W178
W235
W209
W274
W296
W240
W206
W241
W167
W294
W179
W254
W284
W177
W285
W182
W233
W172
W256
W249
W68
W53
W136
W69
W55
W86
W103
W105
W93
W125
W278
W210
W58
W122
W156
W73
W152
W221
W289
W106
W279
W116
W87
W212
W219
W298
W218
W232
W188
W195
W211
W300
W245
W306
W280
W243
W222
W184
W286
W281
W220
W248
W252
W161
W168
W160
W155
W181
W244
W247
W228
W227
W305
W20
W169
W158
W153
W154
W159
W276
W192
W185
W257
W297
W250
W258
W273
W272
W271
W270
W269
W292
W291
W290
W302
W301
W295
W264
W239
W238
W237
W236
W217
W216
W215
W214
W213
W81
W201
W200
W268
W131
W166
W176
W175
W174
W255
W141
W171
W127
W84
W207
W183
W173
W187
W204
W189
W193
W128
W157
W148
W186
W90
W259
W139
W144
W145
W140
W146
W142
W3
W126
W205
W129
W112
W147
W143
W111
W113
W17
W199
W75
W114
W115
W165
W102
W99
W303
W137
W138
W130
W24
W164
W163
W162
W196
W96
W1
19
W134
W133
W132
W121
W246
W108
W107
W120
W61
W62
W67
W78
W71
W45
W9
W60
W10
W66
W63
W64
W65
W308
W251
W191
W26
W27
W77
W74
W261
W266
W11
W7
W8
W43
W149
W151
W170
W194
W229
W234
W190
W299
W197
W5
W44
W57
W260
W198
W304
W34
W35
Lch
Rch
Lch
Rch
C215
C100
C115
C105
K2
K1
TH2
TH1
TH3
R151
R157
C116
R153
C106
R155
R127
R13
R14
L1
W357
C103
C107
C1
13
R137
R224
R129
C25
R121
R100
R24
R2
R1
R23
VR3
C222
C33
C39
C32
C37
C13
C12
C11
C22
C21
C14
C3
C4
C34
C101
C38
C31
VR1
VR2
C123
R26
R161
C27
C26
C29
C30
R133
C40
C28
R217
R143
R219
C9
C209
R135
R123
R215
R141
R139
R149
R145
C207
R221
R21
1
R131
R101
R103
R205
R1
13
R115
R125
C109
R107
R
111
R109
C
111
R105
R1
19
R1
17
R147
C121
R213
R256
R253
R251
R271
C1
18
R160
C1
17
R159
C211
C212
L4
C217
C218
W356
R202
R201
R203
R204
C204
C201
C202
C203
C8
W353
R152
R158
R154
R156
R128
C104
C108
C1
14
R136
R130
R225
R122
VR4
C102
C124
R162
R134
R218
R144
R220
C210
R138
R124
R216
R140
R142
R150
R146
C208
R222
R212
R132
R102
R104
R206
R106
R116
R126
C110
R108
R1
12
R1
10
C1
12
R1
14
R120
R1
18
R148
C122
R214
C205
R207
W358
W355
W352
L3
R280
R226
C216
R223
C214
C213
R254
R265
C224
R269
R266
C226
C227
R264
R263
C223
R261
C225
R268
R262
R255
R257
R252
R277
R276
C231
R273
R274
R272
C229
C228
R210
R209
C230
C221
R267
R228
R227
R260
R230
R229
R233
R234
R270
R281
C206
R164
R259
R258
W351
W354
R242
R243
R241
R163
R236
R235
R237
R238
R25
R10
R15
R16
R17
R18
L2
W359
R240
R239
R406
R9
R11
R12
W360
W267
C232
R231
R232
2
1
9
10
B
21
EE
B
B
E
B
E
B
E
GD S
G
S
DG
S
D
GS
D
GS
D
GS
DG
S
DG
S
D
B
E
E
B
E
B
E
B
B
E
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
B
E
E
B
B
E
E
B
B
E
B
E
B
E
B
E
B
E
E
B
E
B
B
E
1
8
9
16
EB
B
EE
B
E
B
E
B
EB
B
12
E
12
1
2
Refer to the schematic diagram for the value of resistors and capacitors.
PC BOARD (Component side view)
5
6
Ref. No.
IC1
IC2
IC3
IC4
IC5
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
Q11
Q12
Q13
Q14
Q15
Q16
Q17
Q18
Q19
Q20
Q21
Q22
Q23
Q24
Q25
Q26
Q27
Q28
Q29
Add.
3B
6B
4B
5B
4F
7G
7F
3C
5C
2E
6C
2C
5E
1H
1F
1H
1G
1H
1F
1I
1G
4G
4G
4G
4G
3D
4H
4H
4H
4H
4H
6I
Ref. No.
Q30
Q31
Q32
Q33 Q101 Q102 Q103 Q104 Q105 Q106 Q107 Q108 Q109 Q110 Q111 Q112 Q113 Q114 Q115 Q116 Q117 Q118 Q119 Q120 Q121 Q122 Q123 Q124 Q125 Q126 Q127 Q128
Add.
5I
6I
6I
5H
3C
5C
3D
5D
2C
6D
1D
7C
3C
5C
3C
5C
2D
6D
2D
6C
2C
6E
2C
6E
1D
7C
1C
7D
1E
7C
1C
7E