McIntosh C2300 - Technical Description; Silent Audio Switching; Phono Circuitry; Tone Control Circuitry

35 36
TUBE 750643 SCH 1 OF 3
5A
.9V
0V
LEFT
2E
2E
2E
2E
2E
2E
2E
2E
2E
2B
2B
2B
J31:7
J31:6
J31:5
J31:4
J31:3
J31:1
J2:10
J2:11
J2:12
TO MAIN
2E
2E
2E
2B
J31:9
J31:8
J31:2
J2:9
TO MAIN
221k
R6
221k
R5
.1uF
C6
.1uF
C5
221k
R25
221k
R24
2BJ14:5
2BJ14:6
2BJ14:2
2BJ14:12
TUBE LIGHT
5V
-24v
24v
24v
MM
MM
GND
GND
.9V
0V
0V
120V
120V
121V
PHONO AMP
J31:12
236V
J31:11
236V
J31:10
236V
236V
236V
236V
236V
236V
R MM OUT
NC
2BJ14:3
2BJ14:4
2BJ14:1
2BJ14:11
J4:2
J4:1
2B
2B
J3:1
J3:2 2B
2B
-24v
953
R3
110V
47pF
C2
953
R1
110V
47pF
C1
.001uF
C9
75k
R8
.8V
1M
R10
8
6
7
V2B
.001uF
C8
75k
R7
.8V
1M
R9
1.5k
R12
8
6
7
V1B
10uF
C7
1k
R19
121V
22.1k
R22
22.1k
R23
1k
R18
22.1k
R20
22.1k
R21
DS6
DS4
2.21k
R75
2.21k
R76
1uF
C17
1uF
C16
2.21k
R74
236V
236V
236V
236V
NC
L MM OUT
100uF
C4
1.82k
R4
100uF
C3
1.82k
R2
1.5k
R13
200k
R16
100k
R11
200k
R14
2 1
3
Q2
2 1
3
Q1
DS5
31
2
Q8
DS3
J3:7
TUBE ON
R MM IN
L MM IN
10k
R77
J3:9
J3:11
J3:8
TUBE ON
J3:2
J3:1
5
9
4
V1C
5
9
4
V2C
J2:2
J2:1
3
2
1
V2A
J1:1
J1:2
3
2
1
V1A
DS2
.0033uF
C11
1M
R17
100uF
C13
1uF
C15
.0033uF
C10
1M
R15
1uF
C14
J3:10
J3:12
DS1
J5:1
J5:2
J5:8
J5:9
J4:1
J5:3
J5:5
J5:7
J5:6
J5:10
J5:11
J5:12
J4:3
J4:4
J4:2
J5:4
TUBE_LIGHT
TUBE_LIGHT
236V
236V
236V
236V
24V 24V 24V
175V2
175V2
175V2 236V
24V
24V
-24V
236V
24V
24V
220pF
C55
220pF
C56
100uF
C12
0V
0V
12V
0V
0V
0V
.6V
MM
RIGHT
MM PHONO AMP
0V
12AX7A
12AX7A
12AX7A
12AX7A