Cambridge Audio 640A - Input & Tone Circuit Schematics; Tone Control Circuit Diagram

Cambridge Audio Azur 640A Integrated Amplifier
AP12714/5 Input & Tone PCB Schematic (Tone Control)
C1
330p poly
R1
22k
R2
4k7
R3
4k7
R4
8k2
R11
8k2
C6
150n poly
C9
5p
SW1:A
SW-DPDT
DEFEAT
-15V
+15V
R12
10k
R13
10k
C10
330p poly
R20
22k
R42
4k7
R43
4k7
R44
8k2
R45
8k2
C11
150n poly
C15
5p
SW1:B
SW-DPDT
DEFEAT
-15V
+15V
R46
10k
R47
10k
-15V
+15V
C16
47n poly
C17
47n poly
C19
47n poly
C20
47n poly
C24
47n poly
C27
47n poly
C32
100u 25V
C33
100u 25V
+15V
-15V
3
2
1
8
4
U2:A
NE5532
5
6
7
U2:B
NE5532
3
2
1
8
4
U4:A
NE5532
5
6
7
U4:B
NE5532
3
2
1
8
4
U5:A
NE5532
5
6
7
U5:B
NE5532
R CH IN
L CH IN
R CH OUT
L CH OUT
HEADPHONE
SW2:A
SW-DPDT
TAPE
SW2:B
SW-DPDT
TAPE
J1
TERMINAL
J2
TERMINAL
J3
TERMINAL
J4
TERMINAL
SPEAKER SWITCHING
RSW1
RSW2
R
L
GND
LSW1
LSW2
2
4
3
1
7
8
5
CN2
HEADPHONE JACK
J5
TERMINAL
J6
TERMINAL
J7
TERMINAL
C18
22p
C21
22p
C28
10u 16V NP
C29
10u 16V NP
C30
10u 16V NP
C31
10u 16V NP
R52
150k
R54
150k
R59
150k
R60
150k
1
3
2
VR1:A
20K MOTORISED DUAL POT
4
6
5
VR1:B
20K MOTORISED DUAL POT
4
6
5
VR4:B
MN20K BALANCE
1
3
2
VR4:A
MN20K BALANCE
13
2
VR2:A
B20K LINEAR
46
5
VR2:B
B20K LINEAR
13
2
VR3:A
B20K LINEAR
46
5
VR3:B
B20K LINEAR
R61
220R 3W C
R62
470R 1W C
R63
220R 3W C
R64
470R 1W C
1
2
3
4
5
6
CN3
H6 2.54mm
TO POWER AMP
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