McIntosh C2500 Service Manual

31
32
4
AUDIO
751458 SCH 1 of 5
0V
0V
0V
0V
0V
0V
0V
0V
0V
0V
TO BALANCED O UT
AMP
TO BALANCED
MAIN
RIGHT
UNBALANCED
TO ALANCED
LEFT
0V
2.21
R122
RIGHT -
RIGHT +
4.99k
R112
UNBALANCED
22.1k
R114
4.99k
R111
AMP
MAIN
10µF
C105
22.1k
R113
4.99k
R115
0V
47µF
C112
47µF
C223
47µF
C110
47µF
C109
4.99k
R120
4.99kR119
2.21
R124
4.99k
R117
10µF
C106
4.99k
R116
2.21
R121
4.99k
R118
2.21
R123
- BALANCED AMP
+ BALANCED AMP
6
5
7
U11:2
2
3
1
8 4
B+
B-
U11:1
- BALANCED AMP
2
3
1
8 4
B+
B-
U10:1
+ BALANCED AMP
6
5
7
U10:2
15V
15V
-15V
-15V
-15VL1
15VL1
15VR1
-15VR1
15VL1
-15VL1
15VR1
-15VR1
D19
D20
2 3
1 4
K16
2 3
1 4
K14
2 3
1 4
K13
2 3
1 4
K12
2 3
1 4
K11
2 3
1 4
K10
2 3
1 4
K15
2 3
1 4
K9
221
R140
221
R138
221
R139
221
R137
221
R136
221
R135
221
R134
221
R133
5v1
5v1
5v1
5v1
5v1
5v1
5v1
5v1
J11:4
J11:3
J11:2
J11:1
J11:8
J11:7
J11:6
J11:5
J11:9
J11:10
J11:11
J11:12
J11:14
J11:13
J11:15
J11:16
J11:18
J11:17
J2:1
J2:2
J2:3
J2:4
J2:5
J2:6
J2:7
J2:8
J2:9
J2:10
J2:11
J2:12
J2:13
J2:14
J2:15
J2:16
J2:17
J2:18
5
L_MAIN+
L_MAIN-
R_MAIN-
R_MAIN+
47µF
C118
47µF
C119
47µF
C120
47µF
C121
47µF
C122
47µF
C123
47µF
C124
47µF
C117
OUTPUT2
OUTPUT1
.1µF
C113
.1µF
C114
.1µF
C107
.1µF
C108
L-MAIN
R-MAIN
221K
R125
221K
R129
221K
R130
221K
R126
221K
R131
221K
R127
221K
R132
221K
R128
2 LEFT +
2 LEFT -
2 RIGHT +
2 RIGHT -
1 LEFT +
1 LEFT -
1 RIGHT +
1 RIGHT -
10µF
C116
10µF
C115
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
0V
0V
10µF
C50
10µF
C51
10k
R63
100pF
C69
10k
R70
100pF
C68
10k
R69
10µF
C80
10k
R64
20K
R59
20K
R61
20K
R62
20K
R60
6
5
7
U9:2
2
3
1
8 4
B+
B-
U9:1
15VBI
-15VBI
2 3
1 4
K1
2 3
1 4
K5
2 3
1 4
K3
2 3
1 4
K7
2 3
1 4
K2
2 3
1 4
K6
2 3
1 4
K4
2 3
1 4
K8
J2:1
J2:2
J2:3
J2:4
J2:13
J2:14
J2:7
J2:8
J2:9
J2:10
J2:11
J2:12
10µF
C38
10µF
C39
10µF
C40
10µF
C41
10µF
C42
10µF
C43
10µF
C44
10µF
C45
J2:5
J2:6
J2:15
J2:16
J2:18
J2:17
5.0v
5.0v
2 LEFT +
2 LEFT -
2 RIGHT +
2 RIGHT -
1 LEFT +
1 LEFT -
1 RIGHT +
1 RIGHT -
5
J1:1
J1:2
J1:3
J1:4
J1:5
J1:6
J1:7
J1:8
J1:9
J1:10
J1:11
J1:12
J1:13
J1:14
J1:15
J1:16
J1:17
J1:18
BAL1CONTROL
BAL2CONTROL
BAL-L
BAL-R
221K
R47
221K
R48
221K
R49
221K
R50
221K
R51
221K
R52
221K
R53
221K
R54
100K
R75
100K
R76
100pF
C62
100pF
C63
.1µF
C70
.1µF
C71
10µF
C48
10µF
C49
10µF
C79
100pF
C52
100pF
C53
D3
D4
10µF
C76
2.21
R72
2.21
R73
15V
-15V
15VBI
-15VBI
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
FROM BAL ANCE D IN

McIntosh C2500 Specifications

General

Total Harmonic Distortion	0.08%
Signal to Noise Ratio	100dB
Rated Output Voltage	2.5V unbalanced, 5V balanced
Maximum Output Voltage	8V unbalanced, 16V balanced
High Level Voltage Gain	15dB
Type	Vacuum Tube Preamplifier
Inputs	6 unbalanced, 2 balanced, 1 phono MC, 1 phono MM
Outputs	3 unbalanced, 2 balanced
Weight	29 lbs (13.2 kg)
Input Impedance	47k ohms
Phono Voltage Gain	40dB (MM), 60dB (MC)
Frequency Response	+0, -0.5dB from 20Hz to 20, 000Hz +0, -3dB from 10Hz to 100, 000Hz