McIntosh C2500 Service Manual

35
36
4
AUDIO
751458 SCH 3 of 5
51.1
R11
249
R12
INPUT S
0V
R
0V
1.5k
R24
L
3
1
2
Q4
110
R6
3
1
2
Q2
110
R3
3
1
2
Q8
51.1
R13
3
1
2
Q6
22.1
R20
22.1
R19
1.5k
R26
1.5k
R25
1000µF
C8
3
1
2
Q9
1000µF
C7
1.5k
R23
3
1
2
Q17
3
1
2
Q25
499
R32
499
R31
1
4
6
7
8
2
3
5
B+
B-
U2
1
4
6
7
8
2
3
5
B+
B-
U1
1k
R36
1k
R35
3
1
2
Q3
681
R4
681
R5
3
1
2
Q1
249
R14
3
1
2
Q7
3
1
2
Q5
1000µF
C10
1000µF
C9
3
1
2
Q27
2.21k
R34 2.21kR33
22pF
C14
MC PH
1K
R9
1K
R18
1K
R7
1K
R16
MC OUT
MC OUT
22.1
R22
100pF
C2
3
1
2
Q13
1K
R8
1K
R15
3
1
2
Q21
1k
R2
1k
R1
22.1
R21
100pF
C1
1K
R10
1K
R17
499
R30
499
R29
-5VMC
5VMC
MC1 MC2
MC3 MC4
MC1 MC2
MC3 MC4
.0033 µFC13
5VMC
-5VMC
-5VMC
5VMC
-5VMC
5VMC
-5VMC
5VMC15V
-15V
.0033 µF
C12
2
31
IN OUT
U3
3
1
2
IN OUT
U4
.1µF
C16
.1µF
C17
.1µF
C18
.1µF
C19
22pF
C15
1000pF
C5
1000pF
C6
1000pF
C4
1000pF
C3
3
1
2
Q10
3
1
2
Q14
3
1
2
Q18
3
1
2
Q22
3
1
2
Q26
3
1
2
Q23
3
1
2
Q19
3
1
2
Q15
3
1
2
Q11
3
1
2
Q28
3
1
2
Q24
3
1
2
Q20
3
1
2
Q16
3
1
2
Q12
D1
D2
1
TOP
3 5
J1:1
2
BOTT
4
6
J1:2
100µF
C211
100µF
C210
SP1
SP3
SP2
SP4
SP5
SP8
SP6
SP7
MC LEFT
GND
MC LEFT
GND
GND
MC RIGHT
MC RIGHT
GND
GND
10B
10B
10B
RIGHT MC
LEFT MC
Jx:3
TO TU BE
Jx:2
Jx:1
MC Se ction
MC-R
MC-L
GND
GND
3B
3B
3B
J4:6
J4:9
J4:10
3BJ4:8
R MC OUT
L MC OUT
FROM TUBE (MC)
J26:3
J26:5
J26:7
J26:1
J22:1
J22:2
J22:3
OPEN
R402
OPEN
R403
0
R404
221K
R407
1uF
C226
221K
R408
1uF
C227

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