McIntosh C2500 Service Manual page 34

9 TUBE
751461 SCH 1 of 3
L MM IN
J3:1 2B
J1:1
GND
J3:2 2B
J1:2
R MM IN
J4:1 2B
J2:1
GND
J4:2 2B
J2:2
63
Rename high voltage nets to closely match measurements
R11 47.5k
157V 145V
R26 47.5k
C7
10µF
145V
R5
475k
86V
0V
2
12AX7A
C1
47pF
1.2V
18V 18V
R76 R75
4.75k 4.75k
R1
953
DS4 DS1
C3
DS5 DS2 47µF
6.49k .5 %
DS6 DS3
Pulled high on Audio PCB
thru 10k pullup
R77
2
TUBE_LED Q8
145V
10
R6
RIGHT
475k
PHONO AMP
86V
0V
2
12AX7A
C2
47pF
1.2V
4
9
12AX7A
5 V1:3
18V
R3
953
4
9
12AX7A
5 V2:3
C4 R4
4
47µF 6.49k .5%
9
12AX7A
5
V3:3
-18V
157V
LEFT
R20 PHONO AMP
33.2k
157V
C55
C14
10pF
1µF
R14
105V
267k
C5
.047µF
3
Q1
#132352
V1:2
0V
7
V1:1
12AX7A R80
10k
R9
100µF
1V
2.21M
18V
C12
R12
4.75k
75k
R7 1M
R15
C10 R18
C8
.0033µF 2.21k
.001uF
R2
157V
R22
33.2k
157V
C56
C15
10pF
1µF
R16
105V
C6 267k
.047µF
3
Q2
V2:1 7 V2:2
12AX7A
R21
10k
R10
1V
2.21M
18V
C13
R13
100µF
4.75k
R8 75k R17 1M
R19
C9 C11
2.21k
.001uF .0033µF
L MM OUT
R87
2B J2:12
J4:1
1k
GND
2B J2:11
J4:7
GND
2B J2:9
J4:3
MM-OUT-GND
(SHEILD ONLY)
R88
R MM OUT
2B J2:10
1k
J4:5
18V
J5:8
8 J5:1
18V
18V
J5:7
8 J5:2
-18V
J5:6
J5:3
8
-18V
-18V
J5:5
J5:4
8
J5:4 0V
8 J5:5
0V
J5:3
8 J5:6
156V
J5:2
8 J5:7
156V
J5:1
8 J5:8
157V
64