McIntosh C2500 Service Manual

23
24
3
CONTROL
751457 SCH 3 of 5
DGND
1 2
L4
MAIN
10
R10
1
3
2
J13:1
D6
1 2
L13
PASS-THRU
10R141
4
6
5
D28
DGND
1 2
L14
OUT 1
10
R142
1
3
2
D29
1 2
L15
OUT 2
10
R143
4
6
5
D30
1 2
L16
A
10
R144
1
3
2
D31
1 2
L17
B
10
R145
4
6
5
J15:2
D32
POWER CONTROL
22.1
R27
4.75K
R25
3
1
2
Q1
CONTROL
2.21K
R26
.1UF
C31
3
1
2
Q3
3
1
2
Q2
POWER
D44
MAIN_PC-EN
12V
0V
12V_PC
MAIN
MAIN_PC
22.1
R187
4.75K
R181
3
1
2
Q19
CONTROL
2.21K
R183
.1UF
C75
3
1
2
Q15
3
1
2
Q17
POWER
D46
OUT1_PC-EN
12V
0V
OUT 1
OUT1_PC
22.1
R192
4.75K
R189
3
1
2
Q23
CONTROL
2.21K
R190
.1UF
C77
3
1
2
Q21
3
1
2
Q22
POWER
D48
OUT2_PC-EN
12V
0V
OUT 2
OUT2_PC
22.1
R180
4.75K
R177
3
1
2
Q28
CONTROL
2.21K
R178
.1UF
C74
12V
3
1
2
Q12
3
1
2
Q13
POWER
D45
TRIG1-PC-EN
12V
0V
TRIGGER 1
TRIG1_PC
22.1
R188
4.75K
R182
3
1
2
Q20
CONTROL
2.21K
R184
.1UF
C76
12V
3
1
2
Q16
3
1
2
Q18
POWER
D47
TRIG2_PC-EN
12V
0V
TRIGGER 2
TRIG2_PC
MAIN_PC
OUT1_PC
OUT2_PC
TRIG1_PC
TRIG2_PC
PASS THRU IN
221K
R17
DRIVER
221K
R18
3
1
2
Q30
PASS_IN
3
1
2
Q14
22.1K
R179
LIGHT_CTL
0V
22.1 R215
LIGHT_CTL
MAIN_PC-EN
TRIG2_PC-EN
Q3
7
VSS
8
Q1
5
A1
2
A2
3
Q4
9
Q5
10
Q7
12
SDA
15
SCL
14
Q2
6
A0
1
Q0
4
Q6
11
VDD
16
NC
13
U30
22.1K
R208
22.1K
R206
22.1K
R205
22.1K
R202
22.1K
R201
22.1K
R210
22.1K
R209
I2C_SCL
I2C_SDA
3.3V BU
22.1
R211
22.1
R212
22.1K
R203
22.1K
R204
OUT1_PC-EN
OUT2_PC-EN
TRIG1-PC-EN
22.1 R217
22.1 R219
22.1K
R207
Address=1
.1UFC80
MAIN_LIGHT_PC
150
R14
OFF
ON
ON
LIGHTS OFF
3
1
2
Q29
22.1K
R8
LIGHT_CTL
0V
OUT1_LIGHT_PC
150
R15
3
1
2
Q31
22.1K
R222
LIGHT_CTL
0V
OUT2_LIGHT_PC
150
R221
3
1
2
Q32
22.1K
R224
LIGHT_CTL
0V
TR1_LIGHT_PC
150
R223
3
1
2
Q33
22.1K
R226
LIGHT_CTL
0V
TR2_LIGHT_PC
150
R225
MAIN_LIGHT_PC
OUT1_LIGHT_PC
OUT2_LIGHT_PC
TR1_LIGHT_PC
TR2_LIGHT_PC
1 2
L2
1 2
L30
1 2
L31
1 2
L32
1 2
L33
1 2
L34
3.3V BU
LIGHT CTL IN
100K
R198
BUFFER
100K
R199
3
1
2
Q27
LIGHT_CTL_IN
TIP
RING
SLEEVE
LIGHTS OFF
ON
OFF
PASS-THRU ON
SPARE
TIP
RING
SLEEVE
TIP
RING
SLEEVE
TIP
RING
SLEEVE
TIP
RING
SLEEVE
TIP
RING
SLEEVE
(Input)
12V_PC
12V_PC
12V_PC
12V_PC
4.75K
R16
4.75K
R3
4.75K
R9
4.75K
R11
4.75K
R12
(Micro provides pullup)
.1UF
C44
3.3V BU
4
2
1
3
B+
GND
5
U17
3.3V BU
BUFFER
D5
D7
D8
D9
D10
D11
OFF
ON
OFF
ON
LIGHTS OFF
ON
LIGHTS OFF
ON
ON
LIGHTS OFF
ON
LIGHTS OFF
PASS-THRU ON
OFF
OFF
ON
OFF
ON
OFF
ON
OFF
ON
RS232 Enable/
RS232 Shutdown/
Not Used
RS232 ON
RS232 Shutdown
(Micro provides pullup)
22.1K
R251
12V_PC
Must also work when connected
to Darlinton driven output)
J13:2
J14:1
J14:2
J15:1

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