Alto L-20 User manual

Service
MODEL: L-20
www.altoproaudio.com
Version1.0

1
CONTENTS
1. Specification
2. Block Diagram
3. Schematic Diagram
4. Wiring Diagram
5. PCB Layout
6. Exploded Views &Mechanical Parts List
7. BOM

29
8. TECHNICAL SPECIFICATION
Mono input channels
Stereo input channels
Impedances
Equalization
DSP Section
Microphone input electronically balanced, discrete input configuration
Frequency response 10Hz to 55kHz, + 3dB
Distortion (THD & N) 0.005% at 4dBu, 1kHz+
Gain range 0dB to 60dB (MIC)
SNR (Signal to Noise Ratio) 115dB
Line input electronically balanced
Frequency response 10Hz to 55kHz, 3dB
+
Distortion (THD & N) 0.005% at 4dBu, 1kHz+
Sensitivity range +15dBu to 45dBu
Line input Balanced/unbalanced
Frequency response 10Hz to 55kHz, 3dB
+
Distortion (THD & N) 0.005% at +4dBu, 1kHz
Microphone input 1.4kOhm
Channel Insert return 2.5kOhm
All other inputs 10kOhm or greater
Tape out 1kOhm
All other output 120Ohm
Hi shelving +15dB @12kHz
Mid bell (mono) +15dB @100Hz to 8kHz
Low shelving +15dB @80Hz
Low Cut filter 75Hz, 18dB/oct.
Hi Mid (stereo) +15dB @ 3kHz
Mid low (stereo) +15dB @500Hz
A/D and D/A converters 24 bit
DSP resolution 24 bit
Type of effects Hall, Room, Vocal & Plate REVERBS
Mono & Stereo DELAY (max DELAY TIME 650ms)
Chorus, Flanger & Reverb MODULATIONS
REVERB+DELAY, REVERB+CHORUS,
Presets 256
Controls 16-position PRESET Selector
16-position VARIATION selector
PEAK LED
MUTE SWITCH with LED indicator
REVERB+FLANGER combinations
Main Mix Section
Noise (Bus noise) Fader 0 dB, channels muted: 100dBr (ref.:+4dBu)
Fader 0dB, all input channels assigned and set to
UNITY gain: 90dBr (ref.:+4dBu)
Max output +22dBu balanced XLR,
22dBu unbalanced, 1/4" jacks+
AUX Returns gain range - to +15dB
AUX Sends max out +22dBu
1. SPECIFICATION (L-20)

30
Power supply
Main voltage USA/Canada 100 120V~, 60Hz
Europe 210 240V~, 50Hz
U.K./Australia 240V~, 50Hz
Power Consumption 70 watts
Fuse 100 120V~ : T800mAL
210 240V~ : T500mAL
Main connection Standard IEC receptacle
Physical
Net weight
Dimension (W D H)
9.3Kg (20.52lb)
495mm 630mm 40/117mm
(19.48" 24.79" 1.55"/4.6")

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CH2-CH12 IDENTICAL TO CH1
2
1
3
CH1
+48V
3-BAND EQ
12K100Hz-8kHz80
HI PASS
SG/OL
LEFT-BUS RIGHT-BUS AUX1 AUX2
RIGHT-BUS
LEFT-BUS
AUX1
AUX2
STEREO INPUT CHANNELS (CH13-20)
LEFT-BUS
RIGHT-BUS
AUX1
AUX4
MAIN OUT
LEFT-BUS
RIGHT-BUS
TAPE IN
RIGHT
2TK
2TK
LEFT METER
RIGHT METER
75Hz
+/-15db
4-BAND EQ
12K50080
+/-15db
MAIN MIX
MAIN MIX LEFT
T
R
S
MAIN MIX RIGHT
T
R
S
PHONE B
T
R
S
LEVEL
PHONES
LEFT
TAPE OUT
2
1
3
2
1
3
LEVEL
STEREO AUX RTN1 3c
5e
1a
4d
2b
3c
5e
1a
4d
2b
LEVEL
-
+
T
R
S
RN
TN
T
R
S
RN
TN
PAN
PHANTOM
CH1
GAIN
-
+
POWER
-
+
LO (FREQ) HI
AUX2
AUX1
FADER
POST
PRE
BALANCE
FADER
3c
5e
1a
4d
2b
LEFT(MONO)
3c
5e
1a
4d
2b
RIGHT
T
R
S
RN
TN
T
R
S
RN
TN
-
+
-
+
MIC GAIN:0~60dB
LINE IN TRIM:+15dB~-45dB
AFL-L AFL-R SOLO(PFL)
SOLO
ON
()
AFL-L
AFL-R
SOLO(PFL)
SOLO
ON
()
AFL-L
AFL-R
SOLO(PFL)
EFX SEND
LEFT-BUS RIGHT-BUS AUX1 AUX2 AFL-L AFL-R SOLO(PFL) DFX SEND
AFL L
AFL R
SOLO(PFL) PFL LED
LOGIC
SOLO CTRL
SOLO ACTIVE
(LEVEL SET)
SOLO MODE
PFL
()
AFL
()
3c
5e
1a
4d
2b
INSERT T
R
S
RN
TN
SUB1 SUB2 SUB1
SUB2
SUB2
SUB1
AUX SEND1
LEVEL
AUX SEND 4
LEVEL
+4dB/MIC
+4dB/MIC
SUB1
LEVEL
SUB OUT
SUB1
T
R
S
SUB1 TO MIX
RIGHT-BUS
LEFT-BUS
SUB1/2
MAIN MIX
CONTROL ROOM SOURCE
ASSIGN
2TK
RIGHT
LEFT
MID
LO M-H HIL-M
3K
12K50080 3K
SUB3 SUB4
SUB3 SUB4 AUX3 AUX4
SUB4
SUB3
AUX3 AUX4
MUTE
AUX4
AUX3
AUX3
AUX4
-20dB=SG(FLICKER)
+15dB=OL(GLOW)
3c
5e
1a
4d
2b
LINE OUT T
R
S
RN
TN DIRECT OUT
(CH1-CH12 ONLY)
2
1
3
MIC IN
+48V
PHANTOM GAIN
-
+
POWER
CH13/14 &
RIGHT-BUS
LEFT-BUS
SUB2
SUB1
ASSIGN
SUB4
SUB3
AUX2
AUX2
AUX1
POST
PRE
AUX4
AUX3
AUX3
AUX4
SOLO LED
SOLO LED
CH15/16 ONLY
CH'S 17/18 & 19/20 ONLY
STEREO TRIM
-20dB=SG(FLICKER)
+15dB=OL(GLOW)
MUTE
MONITOR
AUX1
AUX1
DFX TO
RIGHT-BUS
STEREO AUX RTN2 3c
5e
1a
4d
2b
3c
5e
1a
4d
2b
LEVEL
-
+
T
R
S
RN
TN
T
R
S
RN
TN -
+
MONITOR
DFX TO
AUX2
LEFT-BUS
STEREO AUX RTN3 3c
5e
1a
4d
2b
3c
5e
1a
4d
2b
LEVEL
-
+
T
R
S
RN
TN
T
R
S
RN
TN -
+
STEREO AUX RTN4 3c
5e
1a
4d
2b
3c
5e
1a
4d
2b
LEVEL
-
+
T
R
S
RN
TN
T
R
S
RN
TN -
+
ASSIGN TO
C-R/PHONES
CTRL/L CTRL/R
SOLO
ON
()
AFL-L
AFL-R
SOLO(PFL)
SOLO LED
RIGHT-BUS
LEFT-BUS
SUB2
SUB1
AUX RTN4
SUB4
SUB3
RIGHT-BUS
LEFT-BUS
CTRL-R-R
CTRL-R-L
(AUX SEND 2/3 IDENTICAL)
AFL-L
AFL-R
SOLO(PFL)
AFL-L
AFL-R
SOLO(PFL)
SOLO
ON
()
SOLO
ON
()
3c
5e
1a
4d
2b
MAIN INSERT
T
R
S
RN
TN
3c
5e
1a
4d
2b
MAIN INSERT
T
R
S
RN
TN
3c
5e
1a
4d
2b
MONO OUTPUT
T
R
S
RN
TN
MONO LEVEL
3c
5e
1a
4d
2b
AUX/DFX SEND
T
R
S
RN
TN
3c
5e
1a
4d
2b
AUX SEND
T
R
S
RN
TN AUX SEND 1/2/3
AUX SEND 4
2TK TO MAIN
2TK TO MAIN
SUB1
SUBMIX 2 3 4 IDENTICAL TO SUB1
(TRIM)
(TRIM)
4-BAND EQ
+/-15db
MIC IN
LINE IN
CTRL ROOM OUTPUT
LEFT
T
R
S
RIGHT
T
R
S
PHONES OUTPUT
PHONE A
T
R
S
LEVEL
CTRL ROOM
SUB3/4
AFL-L
AFL-R
SOLO(PFL)
CTRL/L CTRL/R
FROM SUB2
FROM SUB3
FROM SUB4
DSP BOARD
PRESETS
VARIATIONS
MUTE
DSP FOOTSWITCH
FX OUT L
FX OUT R
CTRL-R-R
CTRL-R-L
DFX SEND
DFX SEND
SG/OL
HI PASS
75Hz
LEFT(MONO)
RIGHT
LEFT(MONO)
RIGHT
LEFT(MONO)
RIGHT
LEFT(MONO)
RIGHT
AUX RETURN
SOLO
ASSIGN TO
RIGHT-BUS
LEFT-BUS
GEQ
GEQ
EQ ON
L20MAP.Sch
Titel
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File:
Date: Drawn By: Sheet
RevisionModel No:
1-Oct-2003 KEVIN LIN.
ALTO MIXING CONSOLE
11 of
L-20 BLOCK DIAGRAM VER030125 A1
LOGIC
AUX2
AUX1
DFX RETURN TO
ALTO L-20
BLOCK DIAGRAM
(PRELIMINARY)
3c
5e
1a
4d
2b SUB1 INSERT
T
S
RN
TN
IDENTICAL TO SUB1 INSERTSUBINSERT 2 3 4
DFX OUT T
R
S
2. Block Diagram

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L12PU1.Sch
Titel
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Date: Drawn By: Sheet
RevisionModel No:
1-Oct-2003 BOW
12 of
ALTO L12 VER030530
A3
PCB# L12PU1.PCB
L12PU1(1/2)
L12PU1
L12PU1-2.SCH
3c
5e
1a
4d
2b
X4
JY-6351G-02-250
R6
120R
R8
120R
CTRL ROOM OUT
3c
5e
1a
4d
2b
X3
JY-6351G-02-250
R7
120R
R5
120R
LEFT
RIGHT
CTRL-R-L
CTRL-R-R
CTRL-R-R
CTRL-R-L
3c
5e
1a
4d
2b
X5
JY-6351G-02-250
T
R
S
RN
TN MAIN-INS-L
INS1
RTN1
R9
120R
3c
5e
1a
4d
2b
X6
JY-6351G-02-250
T
R
S
RN
TN MAIN-INS-R
INS2
RTN2
R10
120R
MAIN-INS-L
MAIN-INS-R
MAIN-L
MAIN-R
MAIN-INSERT
3c
5e
1a
4d
2b
X19
JY-6351G-02-250
AUX SEND1
R40
120R
R39
120R
3c
5e
1a
4d
2b
X20
JY-6351G-02-250
AUX SEND2
R38
120R
R42
120R
T
R
S
RN
TN
T
R
S
RN
TN
AUXSEND1
AUXSEND2
3c
5e
1a
4d
2b
X24
JY-6351G-02-250
AUX SEND3
R41
120R
R47
120R
3c
5e
1a
4d
2b
X25
JY-6351G-02-250
AUX SEND4
R46
120R
R48
120R
T
R
S
RN
TN
T
R
S
RN
TN
AUXSEND3
AUXSEND4
AUXSEND1
AUXSEND2
AUXSEND3
AUXSEND4
AUX SEND
MAIN-INS-L
MAIN-INS-R
MAIN-R-3
MAIN-L-3
MAIN-L
MAIN-R
MONO-LEVEL
CTRL-R-R
CTRL-R-L
DFXOUT-L
DFXOUT-R
AUXRTN1-L
AUXRTN1-R
AUXRTN2-R
AUXRTN2-L
AUXRTN3-R
AUXRTN3-L
AUXRTN4-R
AUXRTN4-L
AUXSEND1
AUXSEND2
AUXSEND3
AUXSEND4
SUB1-L
SUB2-R
SUB3-L
SUB4-R
+VCC
-VCC
(TO L12MN1)
(TO L12MN1)
C2
47u/25V
5
67
U1B
4580M
R50
36K
C4
22P
C3
47u/25V
VR1
W50K
R55
30K
C1
47u/25V R49
3K6
MONO-LEVEL
3c
5e
1a
4d
2b
X21
JY-6351G-02-250
T
R
S
RN
TN
MONO
R43
120R
R27
120R
C6
100n
C5
100n
84
U1C
4580M
+VCC
-VCC
3c
5e
1a
4d
2b
X34
JY-6351G-02-250
FOOTSWITCH
DIRECT
3c
5e
1a
4d
2b
X7
JY-6351G-02-250
DIRECT1
R15
120R
R12
120R
T
R
S
RN
TN
DIRECT1
DIR-OUT1
3c
5e
1a
4d
2b
X8
JY-6351G-02-250
DIRECT2
R16
120R
R13
120R
T
R
S
RN
TN
DIRECT2
DIR-OUT2
3c
5e
1a
4d
2b
X9
JY-6351G-02-250
DIRECT3
R17
120R
R14
120R
T
R
S
RN
TN
DIRECT3
DIR-OUT3
3c
5e
1a
4d
2b
X18
JY-6351G-02-250
DIRECT4
R18
120R
R37
120R
T
R
S
RN
TN
DIRECT4
DIR-OUT4
3c
5e
1a
4d
2b
X35
JY-6351G-02-250
DFX OUT
DFXOUT-L
DFXOUT-R
R56
120R
R57
120R
MAIN-R-2
MAIN-L-2
FOOTSW
FOOTSW
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
CN3
2.0-18P-B24A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
CN2
2.5-14P-B24A
EFXRTN-L
EFXRTN-R
3. Schematic Diagram

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Titel
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Date: Drawn By: Sheet
RevisionModel No:
11-Jun-2003 BOW
22of
ALTO L12 VER030530
A3
PCB# L12MN1.PCB
L12PU1-2(2/2)
3c
5e
1a
4d
2b
X16
JY-6351G-02-250
R
T
S
RN
TN MAIN R (UNBAL)
3c
5e
1a
4d
2b
X17
JY-6351G-02-250
T
R
S
RN
TN MAIN L (UNBAL)
R36
120R
R11
120R
R34
120R
R35
120R
(BALANCED)
2
1
3
X32
JY-5030-030G
2
1
3
X33
JY-5030-030G
MAIN OUT
RIGHT
LEFT
1
2
3
SW1A
PS-42E85L
7
8
9
P
SW1C
PS-42E85L
4
5
6
P
SW1B
PS-42E85L
10
11
12
P
SW1D
PS-42E85L
R28
120R
R29
120R
R51
5K1
R30
120R
R44
120R
R54
5K1
R31
120R
R32
120R
R53
5K1
R33
120R
R45
120R
R52 5K1
MAIN-R-3
MAIN-R-2
MAIN-L-3
MAIN-L-2
DIR-OUT1
DIR-OUT2
DIR-OUT3
DIR-OUT4
(TO L12PU2)
MAIN-R-2
MAIN-L-2
MAIN-R-3
MAIN-L-3
3c
5e
1a
4d
2b
X22
JY-6351G-02-250
STEREO AUX
LEFT 1
3c
5e
1a
4d
2b
X26
JY-6351G-02-250
RIGHT 1
RETURN1
(MONO)
AUXRTN1-L
AUXRTN1-R
AUXRTN1-L
AUXRTN1-R
3c
5e
1a
4d
2b
X27
JY-6351G-02-250
STEREO AUX
LEFT 2
3c
5e
1a
4d
2b
X28
JY-6351G-02-250
RIGHT 2
RETURN2
(MONO)
AUXRTN2-L
AUXRTN2-R AUXRTN2-R
AUXRTN2-L
3c
5e
1a
4d
2b
X23
JY-6351G-02-250
STEREO AUX
LEFT 3
3c
5e
1a
4d
2b
X29
JY-6351G-02-250
RIGHT 3
RETURN3
(MONO)
AUXRTN3-L
AUXRTN3-R AUXRTN3-R
AUXRTN3-L
3c
5e
1a
4d
2b
X30
JY-6351G-02-250
STEREO AUX
LEFT 4
3c
5e
1a
4d
2b
X31
JY-6351G-02-250
RIGHT 4
RETURN4
(MONO)
AUXRTN4-R
AUXRTN4-L
STEREO AUX RETURN
3c
5e
1a
4d
2b
X13
JY-6351G-02-250
T
R
S
RN
TN
SUB-INS3
R23
120R
3c
5e
1a
4d
2b
X2
JY-6351G-02-250
T
R
S
RN
TN
INSERT-SUB3
R4
120R
R3
120R
SUB2-R
SUB3-L
SUB4-R
3c
5e
1a
4d
2b
X15
JY-6351G-02-250
T
R
S
RN
TN
SUB-INS4
R24
120R
3c
5e
1a
4d
2b
X14
JY-6351G-02-250
T
R
S
RN
TN
INSERT-SUB4
R26
120R
R25
120R
3c
5e
1a
4d
2b
X10
JY-6351G-02-250
T
R
S
RN
TN
SUB-INS1
R19
120R
3c
5e
1a
4d
2b
X1
JY-6351G-02-250
T
R
S
RN
TN
INSERT-SUB1
R2
120R
R1
120R
SUB1-L
3c
5e
1a
4d
2b
X12
JY-6351G-02-250
T
R
S
RN
TN
SUB-INS2
R20
120R
3c
5e
1a
4d
2b
X11
JY-6351G-02-250
T
R
S
RN
TN
INSERT-SUB2
R22
120R
R21
120R
EFXRTN-L
EFXRTN-R
1
2
3
4
5
CN1
2.5-14P-B24A

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L12PU2.Sch
Titel
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File:
Date: Drawn By: Sheet
RevisionModel No:
11-Jun-2003 BOW
MAIN INPUT STAGE
21of
ALTO L12 VER030530
A3
PCB# L12PU2.PCB
L12PU2
PU2
L12PU2-2.SCH
R10_1
4R7
TRIM2-CH2
R11_1
4R7
TRIM1-CH2
C15_1
1n
INS2-CH2
C14_1
1n
C19_1
1000u/10V
R12_1
4R7
R15_1
1K50
R3_1
2K49
L-CUT2-ON
3
21
U2_1A
4580M
L-CUT2-OF
R25_1
5K11
INS1-CH2
C6_1
22P
C7_1
47u/25V
5
67
U2_1B
4580M
R30_1
62K
R28_1
1K3
R19_1
20K
R18_1
20K
C8_1
47u/25V
C16_1
0.22u/50V
C17_1
0.22u/50V
C18_1
0.22u/50V
R29_1
6K8
2
1
3
4
X3_1
JY-5042-030G
3c
5e
1a
4d
2b
X1_1
JY-6351G-02-250
T
R
S
RN
TN
INSERT 2
3c
5e
1a
4d
2b
X2_1
JY-6351G-02-250
C11_1
330P
LINE IN GAIN=+15~-45dB
C1_1
10n
MIC GAIN=0~-60dB
R20_1
470R
R7_1
2K49
C13_1
47u/63V
C12_1
47u/63V
R14_1
5K62
R13_1
5K62
C3_1
22P
C9_1
22u/35V
R24_1
5K11
C10_1
22u/35V R27_1
10K0
R26_1
10K0
R2_1
6K81
R1_1
6K81
LINE IN2
MIC 2
PH PWR
TR3_1
HR
TR1_1
A1316
R16_1
1K50
-VCC
+VCC
-VCC
R4_1
2K49
R17_1
20K
R9_1
2K49
C2_1
10n
R21_1
470R
TR4_1
HR
+VCC
TR2_1
A1316
-VCC
+VCC
D1_1
BAS316
R5_1
2K49
+VCC
TR5_1
HR
R6_1
2K49
-VCC
R8_1
2K49
R22_1
5K11
R23_1
5K11
C4_1
22P
C5_1
22P
5
67
U1_1B
4580M
3
21
U1_1A
4580M
R10_2
4R7
TRIM2-CH3
R11_2
4R7
TRIM1-CH3
C15_2
1n
INS2-CH3
C14_2
1n
C19_2
1000u/10V
R12_2
4R7
R15_2
1K50
R3_2
2K49
L-CUT3-ON
3
21
U2_2A
4580M
L-CUT3-OF
R25_2
5K11
INS1-CH3
C6_2
22P
C7_2
47u/25V
5
67
U2_2B
4580M
R30_2
62K
R28_2
1K3
R19_2
20K
R18_2
20K
C8_2
47u/25V
C16_2
0.22u/50V
C17_2
0.22u/50V
C18_2
0.22u/50V
R29_2
6K8
2
1
3
4
X3_2
JY-5042-030G
3c
5e
1a
4d
2b
X1_2
JY-6351G-02-250
T
R
S
RN
TN
INSERT 3
3c
5e
1a
4d
2b
X2_2
JY-6351G-02-250
C11_2
330P
LINE IN GAIN=+15~-45dB
C1_2
10n
MIC GAIN=0~-60dB
R20_2
470R
R7_2
2K49
C13_2
47u/63V
C12_2
47u/63V
R14_2
5K62
R13_2
5K62
C3_2
22P
C9_2
22u/35V
R24_2
5K11
C10_2
22u/35V R27_2
10K0
R26_2
10K0
R2_2
6K81
R1_2
6K81
LINE IN3
MIC 3
PH PWR
TR3_2
HR
TR1_2
A1316
R16_2
1K50
-VCC
+VCC
-VCC
R4_2
2K49
R17_2
20K
R9_2
2K49
C2_2
10n
R21_2
470R
TR4_2
HR
+VCC
TR2_2
A1316
-VCC
+VCC
D1_2
BAS316
R5_2
2K49
+VCC
TR5_2
HR
R6_2
2K49
-VCC
R8_2
2K49
R22_2
5K11
R23_2
5K11
C4_2
22P
C5_2
22P
5
67
U1_2B
4580M
3
21
U1_2A
4580M
R10_3
4R7
TRIM2-CH4
R11_3
4R7
TRIM1-CH4
C15_3
1n
INS2-CH4
C14_3
1n
C19_3
1000u/10V
R12_3
4R7
R15_3
1K50
R3_3
2K49
L-CUT4-ON
3
21
U2_3A
4580M
L-CUT4-OF
R25_3
5K11
INS1-CH4
C6_3
22P
C7_3
47u/25V
5
67
U2_3B
4580M
R30_3
62K
R28_3
1K3
R19_3
20K
R18_3
20K
C8_3
47u/25V
C16_3
0.22u/50V
C17_3
0.22u/50V
C18_3
0.22u/50V
R29_3
6K8
2
1
3
4
X3_3
JY-5042-030G
3c
5e
1a
4d
2b
X1_3
JY-6351G-02-250
T
R
S
RN
TN
INSERT 4
3c
5e
1a
4d
2b
X2_3
JY-6351G-02-250
C11_3
330P
LINE IN GAIN=+15~-45dB
C1_3
10n
MIC GAIN=0~-60dB
R20_3
470R
R7_3
2K49
C13_3
47u/63V
C12_3
47u/63V
R14_3
5K62
R13_3
5K62
C3_3
22P
C9_3
22u/35V
R24_3
5K11
C10_3
22u/35V R27_3
10K0
R26_3
10K0
R2_3
6K81
R1_3
6K81
LINE IN4
MIC 4
PH PWR
TR3_3
HR
TR1_3
A1316
R16_3
1K50
-VCC
+VCC
-VCC
R4_3
2K49
R17_3
20K
R9_3
2K49
C2_3
10n
R21_3
470R
TR4_3
HR
+VCC
TR2_3
A1316
-VCC
+VCC
D1_3
BAS316
R5_3
2K49
+VCC
TR5_3
HR
R6_3
2K49
-VCC
R8_3
2K49
R22_3
5K11
R23_3
5K11
C4_3
22P
C5_3
22P
5
67
U1_3B
4580M
3
21
U1_3A
4580M
R10
4R7
TRIM2-CH1
R11
4R7
TRIM1-CH1
C15
1n
INS2-CH1
C14
1n
C19
1000u/10V
R12
4R7
R15
1K50
R3
2K49
L-CUT1-ON
3
21
U2A
4580M
L-CUT1-OF
R25
5K11
INS1-CH1
C6
22P
C7
47u/25V
5
67
U2B
4580M
R30
62K
R28
1K3
R19
20K
R18
20K
C8
47u/25V
C16
0.22u/50V
C17
0.22u/50V
C18
0.22u/50V
R29
6K8
2
1
3
4
X3
JY-5042-030G
3c
5e
1a
4d
2b
X1
JY-6351G-02-250
T
R
S
RN
TN
INSERT 1
3c
5e
1a
4d
2b
X2
JY-6351G-02-250
C11
330P
LINE IN GAIN=+15~-45dB
C1
10n
MIC GAIN=0~-60dB
R20
470R
R7
2K49
C13
47u/63V
C12
47u/63V
R14
5K62
R13
5K62
C3
22P
C9
22u/35V
R24
5K11
C10
22u/35V R27
10K0
R26
10K0
R2
6K81
R1
6K81
LINE IN1
MIC 1
PH PWR
TR3
HR
TR1
A1316
R16
1K50
-VCC
+VCC
-VCC
R4
2K49
R17
20K
R9
2K49
C2
10n
R21
470R
TR4
HR
+VCC
TR2
A1316
-VCC
+VCC
D1
BAS316
R5
2K49
+VCC
TR5
HR
R6
2K49
-VCC
R8
2K49
R22
5K11
R23
5K11
C4
22P
C5
22P
5
67
U1B
4580M
3
21
U1A
4580M
3c
5e
1a
4d
2b
X4
JY-6351G-02-250
T
R
S
RN
TN
LINE IN 5/6
3c
5e
1a
4d
2b
X5
JY-6351G-02-250
T
R
S
RN
TN
LEFT(MONO)
RIGHT
3
21
U5A
NJM4580M
R72
22K
C48
22P
C56
47u/25V
R70
10K
C47
22P
R66
18K
C58
100P
R68
18K
C61
100P
5
67
U5B
NJM4580M
R74
22K
C49
22P
C57
47u/25V
R71
10K
C46
22P
R67
18K
C59
100P
R69
18K
C60
100P
R73
20K
R75
20K
R45
20K
R46
20K
R47
20K
R35
4R7
TRIM2-CH5
R36
4R7
TRIM1-CH5
C41
1n
C40
1n
C53
1000u/10V
R37
4R7
R40
1K50
R49
2K49
L-CUT5-ON
3
21
U4A
4580M
L-CUT5-OF
R60
5K11
C45
22P
C54
47u/25V
5
67
U4B
4580M
R63
62K
R64
1K3
R44
20K
R43
20K
C55
47u/25V
C50
0.22u/50V
C51
0.22u/50V
C52
0.22u/50V
R65
6K8
2
1
3
4
X6
JY-5042-030G
C62
330P
C38
10n
R55
470R
R48
2K49
C37
47u/63V
C36
47u/63V
C44
22P
R59
5K11
R62
10K0
R61
10K0
R39
6K81
R38
6K81
MIC 5/6
PH PWR
TR8
HR
TR6
A1316
R41
1K50
-VCC
+VCC
-VCC
R51
2K49
R42
20K
R50
2K49
C39
10n
R56
470R
TR9
HR
+VCC
TR7
A1316
-VCC
+VCC
D2
BAS316
R52
2K49
+VCC
TR10
HR
R54
2K49
-VCC
R53
2K49
R57
5K11
R58
5K11
C42
22P
C43
22P
5
67
U3B
4580M
3
21
U3A
4580M
INS-CH5-6
INS-CH5
INS-CH6
3c
5e
1a
4d
2b
X4_1
JY-6351G-02-250
T
R
S
RN
TN
LINE IN 7/8
3c
5e
1a
4d
2b
X5_1
JY-6351G-02-250
T
R
S
RN
TN
LEFT(MONO)
RIGHT
3
21
U5_1A
NJM4580M
R72_1
22K
C48_1
22P
C56_1
47u/25V
R70_1
10K
C47_1
22P
R66_1
18K
C58_1
100P
R68_1
18K
C61_1
100P
5
67
U5_1B
NJM4580M
R74_1
22K
C49_1
22P
C57_1
47u/25V
R71_1
10K
C46_1
22P
R67_1
18K
C59_1
100P
R69_1
18K
C60_1
100P
R73_1
20K
R75_1
20K
R45_1
20K
R46_1
20K
R47_1
20K
R35_1
4R7
TRIM2-CH7
R36_1
4R7
TRIM1-CH7
C41_1
1n
C40_1
1n
C53_1
1000u/10V
R37_1
4R7
R40_1
1K50
R49_1
2K49
L-CUT7-ON
3
21
U4_1A
4580M
L-CUT7-OF
R60_1
5K11
C45_1
22P
C54_1
47u/25V
5
67
U4_1B
4580M
R63_1
62K
R64_1
1K3
R44_1
20K
R43_1
20K
C55_1
47u/25V
C50_1
0.22u/50V
C51_1
0.22u/50V
C52_1
0.22u/50V
R65_1
6K8
2
1
3
4
X6_1
JY-5042-030G
C62_1
330P
C38_1
10n
R55_1
470R
R48_1
2K49
C37_1
47u/63V
C36_1
47u/63V
C44_1
22P
R59_1
5K11
R62_1
10K0
R61_1
10K0
R39_1
6K81
R38_1
6K81
MIC 7/8
PH PWR
TR8_1
HR
TR6_1
A1316
R41_1
1K50
-VCC
+VCC
-VCC
R51_1
2K49
R42_1
20K
R50_1
2K49
C39_1
10n
R56_1
470R
TR9_1
HR
+VCC
TR7_1
A1316
-VCC
+VCC
D2_1
BAS316
R52_1
2K49
+VCC
TR10_1
HR
R54_1
2K49
-VCC
R53_1
2K49
R57_1
5K11
R58_1
5K11
C42_1
22P
C43_1
22P
5
67
U3_1B
4580M
3
21
U3_1A
4580M
INS-CH7-8
INS-CH7
INS-CH8
R104
120R
R104_1
120R
R104_2
120R
R104_3
120R

12345678910 11 12
A
B
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D
12
1110987654321
D
C
B
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L12PU2-2.Sch
Titel
Size
File:
Date: Drawn By: Sheet
RevisionModel No:
11-Jun-2003 BOW
MAIN INPUT STAGE
22of
ALTO L12 VER030530
A4
PCB# L12PU2.PCB
L12PU2-2
C63
100n
C64
100n
C65
100n
C66
100n
C67
100n
C68
100n
C69
100n
C70
100n
84
U1_1C
4580M
84
U2_1C
4580M
84
U2C
4580M
84
U1C
4580M
+VCC
-VCC
C71
100n
C72
100n
C73
100n
C74
100n
C75
100n
C76
100n
C77
100n
C78
100n
84
U1_3C
4580M
84
U2_3C
4580M
84
U2_2C
4580M
84
U1_2C
4580M
(TO L12MN1)
+VCC
-VCC
TRIM2-CH1
TRIM1-CH1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN2
2.5-14P-B24A
INS2-CH1
INS1-CH4
L-CUT1-ON
L-CUT4-OF
L-CUT1-OF
L-CUT4-ON
INS1-CH1
INS2-CH4
TRIM1-CH4
PH PWR
TRIM2-CH4
TRIM2-CH2
INS1-CH3
TRIM1-CH2
L-CUT3-OF
INS2-CH2
L-CUT3-ON
L-CUT2-ON
INS2-CH3
L-CUT2-OF
TRIM1-CH3
INS1-CH2
TRIM2-CH3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN1
2.5-14P-B24A
(TO L12MN1)
84
U3C
4580M
84
U4C
4580M
84
U5C
4580M
84
U3_1C
4580M
84
U4_1C
4580M
84
U5_1C
4580M
C25
100n C27 100n C29 100n C31 100n C33 100n C35 100n
C24
100n C26 100n C28 100n C30 100n C32 100n C34 100n
3c
5e
1a
4d
2b
X7
JY-6351G-02-250
T
R
S
RN
TN
LINE IN 9
3c
5e
1a
4d
2b
X8
JY-6351G-02-250
T
R
S
RN
TN
LEFT(MONO)
RIGHT
3
21
U6A
4580M
R88
20K
C103
22P
C107
47u/25V
R84
10K
C99
22P
R76
10K
C91
100P
R78
10K
C93
100P
5
67
U6B
4580M
R90
20K
C105
22P
C109
47u/25V
R86
10K
C101
22P
R80
10K
C95
100P
R82
10K
C97
100P
LINE IN 10
3c
5e
1a
4d
2b
X9
JY-6351G-02-250
T
R
S
RN
TN
LINE IN 11
3c
5e
1a
4d
2b
X10
JY-6351G-02-250
T
R
S
RN
TN
LEFT(MONO)
RIGHT
3
21
U7A
4580M
R89
20K
C104
22P
C108
47u/25V
R85
10K
C100
22P
R77
10K
C92
100P
R79
10K
C94
100P
5
67
U7B
4580M
R91
20K
C106
22P
C110
47u/25V
R87
10K
C102
22P
R81
10K
C96
100P
R83
10K
C98
100P
LINE IN 12
(TO L12MN1)
TRIM2-CH5
TRIM1-CH5
L-CUT5-ON
L-CUT5-OF
INS-CH5
INS-CH6
TRIM2-CH7
TRIM1-CH7
L-CUT7-ON
L-CUT7-OF
INS-CH7
INS-CH8
84
U6C
4580M
84
U7C
4580M
84
U11C
4580M
84
U10C
4580M
84
U8C
4580M
84
U9C
4580M
C80
100n C82 100n C84 100n C86 100n C88 100n
C90
100n
C79
100n C81 100n C83 100n C85 100n C87 100n
C89
100n
INS-CH5-6
INS-CH7-8
PHONES-L
PHONES-R
2TKIN-R
2TKIN-L
MAIN-R-3
MAIN-L-3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN4
2.5-14P-B24A
(TO L12MN1)
+VCC
-VCC
INS-CH9
INS-CH10
INS-CH11
INS-CH12
INS-CH9
INS-CH10
INS-CH11
INS-CH12
MAIN-L-3
MAIN-R-3
2TKIN-L
2TKIN-R
1 4
2 5
3 6
X13
SCP6873NS3232
TAPE OUTTAPE IN
R(RED)
L(WHITE)
R32
1K
R31
1K
PHONES-R
PHONES-L PHONES OUTPUT
C112
22P
R93
10K
5
67
U10B
BA15218N
3
21
U10A
BA15218N
R97
120R
R99
120R
PHONES B
R103
120R
3c
5e
1a
4d
2b
X12
JY-6351G-02-250
R101
120R
R95
10K
C114
22P
5
67
U11B
BA15218N
3
21
U11A
BA15218N
C111
22P
R92
10K
5
67
U8B
BA15218N
3
21
U8A
BA15218N
R96
120R
R98
120R
PHONES A
R102
120R
3c
5e
1a
4d
2b
X11
JY-6351G-02-250
R100
120R
R94
10K
C113
22P
5
67
U9B
BA15218N
3
21
U9A
BA15218N
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
CN3
2.5-14P-B24A

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D
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L12MN2.Sch
Titel
Size
File:
Date: Drawn By: Sheet
RevisionModel No:
11-Jun-2003 BOW
51of
ALTO L12 VER030530
A4
PCB# L12MN2.PCB
L12MN2(1/5)
CH1
CH1.SCH
CH2
CH2.SCH
CH3
CH3.SCH
CH4
CH4.SCH
-VCC
+VCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
CN4
2.5-14P-B24A
AUX2
AUX4
AFL-R
AFL-L
SUB4
SUB3
LOGIC
SOLO(PFL)
SUB2
SUB1
RIGHT-BUS
LEFT-BUS
AUX3
AUX1
PH PWR
(TO L12MN1) (TO L12PU2)
TRIM2-CH1
TRIM1-CH1
INS2-CH1
L-CUT1-ON
L-CUT1-OF
INS1-CH1
PH PWR
TRIM2-CH2
TRIM1-CH2
INS2-CH2
L-CUT2-ON
L-CUT2-OF
INS1-CH2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN1
2.0-14P-B24A
+VCC
-VCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN2
2.0-14P-B24A
INS1-CH4
L-CUT4-OF
L-CUT4-ON
INS2-CH4
TRIM1-CH4
TRIM2-CH4
INS1-CH3
L-CUT3-OF
L-CUT3-ON
INS2-CH3
TRIM1-CH3
TRIM2-CH3
(TO L12PU2)
DIR-OUT1
DIR-OUT2
DIR-OUT3
DIR-OUT4
(TO L12PU1)
1
2
3
4
5
CN3
2.0-5P-B24A
PGND
+VCC
-VCC
R53
47R
R52
47R C26
47uF
C27
47uF PGND
C24
47uF
C25
47uF
84
U3C
4580M
C14
100n
C16
100n
PGND
84
U4C
LM393
C15
100n
C14_1
100n
84
U4_1C
LM393
84
U3_2C
4580M
C14_2
100n
C16_2
100n
84
U4_2C
LM393
C15_2
100n
C14_3
100n
84
U4_3C
LM393
+RVCC
-RVCC

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7654321
D
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CH1.Sch
Titel
Size
File:
Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW
52of
ALTO L12 VER030712
A3
PCB# L12MN2.PCB
L12MN2-CH1(2/5)
R16
6K8
VR7
W50K
AUX1
R7
5K1
5
67
U2B
4580M
VR5A
10KD
R20
12K
C9
22P
VR9
W50K
C4
47u/25V
R14
6K8
AUX3
LEVEL
AUX-POST
R8
5K1
R9
5K1
LEFT-BUS
RIGHT-BUS
PAN
AUX-PRE
21
3
SW7A
PS-22E85L
54
6
SW7B
PS-22E85L
21
3
SW3A
PS-22E85L
54
6
SW3B
PS-22E85L
21
3
SW6A
PS-22E85L
54
6
SW6B
PS-22E85L
54
6
SW4B
PS-42E85L
21
3
SW4A
PS-42E85L
SUB1
SUB2
R10
5K1
R11
5K1
AUX1/2 PRE/POST
R5
10K
SOLO(PFL)
D1
BAS316
LOGIC
LD1
YEL
(SOLO)
R23
2K2
-VCC
(LOGIC=2.0V or 0.5V)
84
U1C
4580M
C17
100n
+VCC
-VCC
LOGIC
EQ HI (12K)
C7
6.8n(M) VR1
B50K
R25
5K6
VR4
B50K
R24
5K6 LO (80Hz)
R4
10K
3
21
U2A
4580M
R19
1M
C6
22P
R18
3K9
VR2
B50K MID (FREQ=100Hz-8K)
C11
33n(M) C12
33n(M)
C8
6.8n(M)
C3
47u/25V
C2
47u/25V
INS2-CH1 INS2-CH1
3
21
U1A
4580M
5
67
U1B
4580M
R2
10K R3 10K
C5 22P
C10
152(M)
R6
5K1
R1
3K
VR3B
500KC
VR3A
500KC
R22
6K2
C1
682(M)
R21
6K2
21
3
SW5A
PS-22E85L
54
6
SW5B
PS-22E85L
SUB3
SUB4
R12
5K1
R13
5K1
87
9
SW4C
PS-42E85L
11 10
12
SW4D
PS-42E85L
AFL-L
AFL-R
R27
6K8
R28
6K8
VR8
W50K
R15
6K8
AUX4
AUX-POST
R17
6K8
AUX2
VR10
W50K
AUX-PRE
5
4
6
SW1B
PS-22E85L-2
2
1
3
SW1A
PS-22E85L-2
LD2
RED
R26
3K3
+VCC
MUTE
2
1
3
SW2A
SW PS-22E85L-2
L-CUT1-OF
L-CUT1-ON INS1-CH1
TRIM2-CH1
TRIM1-CH1
TRIM-CH1
LO-CUT-CH1
VR11
O10K
DIR-OUT1
84
U2C
4580M
C18
100n
C19
100n
C20
100n
R40
15K
VR6
W50K
R29
4K7
R30
4K7
R49
4K7
+RVCC
R47
10K
R46
10K
R45
10K
R41
100K
R42
100K C21
1uF R43
8K2
PGND PGND
PGND
PGND
LD3
LED-2P
TR1
HR
R44
82R
1
2
3
4
8
U4A
393
5
67
U4B
393
R50
27K
R51
1K
3
21
U3A
4580M
PGND
綠紅
D2
4148
D3
4148
C22
1uF
PGND
D4
4148
PGND
+RVCC
TR2
7002
R48
10K
C23
470P
C28
47u/25V

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Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW
53of
ALTO L12 VER030712
A3
PCB# L12MN2.PCB
L12MN2CH2(3/5)
R16_1
6K8
VR7_1
W50K
AUX1
R7_1
5K1
5
67
U2_1B
4580M
VR5_1A
10KD
R20_1
12K
C9_1
22P
VR9_1
W50K
C4_1
47u/25V
R14_1
6K8
AUX3
LEVEL
AUX-POST
R8_1
5K1
R9_1
5K1
LEFT-BUS
RIGHT-BUS
PAN
AUX-PRE
21
3
SW7_1A
PS-22E85L
54
6
SW7_1B
PS-22E85L
21
3
SW3_1A
PS-22E85L
54
6
SW3_1B
PS-22E85L
21
3
SW6_1A
PS-22E85L
54
6
SW6_1B
PS-22E85L
54
6
SW4_1B
PS-42E85L
21
3
SW4_1A
PS-42E85L
SUB1
SUB2
R10_1
5K1
R11_1
5K1
AUX1/2 PRE/POST
R5_1
10K
SOLO(PFL)
D1_1
BAS316
LOGIC
LD1_1
YEL
(SOLO)
R23_1
2K2
-VCC
(LOGIC=2.0V or 0.5V)
84
U1_1C
4580M
C17_1
100n
+VCC
-VCC
LOGIC
EQ HI (12K)
C7_1
6.8n(M) VR1_1
B50K
R25_1
5K6
VR4_1
B50K
R24_1
5K6 LO (80Hz)
R4_1
10K
3
21
U2_1A
4580M
R19_1
1M
C6_1
22P
R18_1
3K9
VR2_1
B50K MID (FREQ=100Hz-8K)
C11_1
33n(M) C12_1
33n(M)
C8_1
6.8n(M)
C3_1
47u/25V
C2_1
47u/25V
INS2-CH2 INS2-CH2
3
21
U1_1A
4580M
5
67
U1_1B
4580M
R2_1
10K R3_1 10K
C5_1 22P
C10_1
152(M)
R6_1
5K1
R1_1
3K
VR3_1B
500KC
VR3_1A
500KC
R22_1
6K2
C1_1
682(M)
R21_1
6K2
21
3
SW5_1A
PS-22E85L
54
6
SW5_1B
PS-22E85L
SUB3
SUB4
R12_1
5K1
R13_1
5K1
87
9
SW4_1C
PS-42E85L
11 10
12
SW4_1D
PS-42E85L
AFL-L
AFL-R
R27_1
6K8
R28_1
6K8
VR8_1
W50K
R15_1
6K8
AUX4
AUX-POST
R17_1
6K8
AUX2
VR10_1
W50K
AUX-PRE
5
4
6
SW1_1B
PS-22E85L-2
2
1
3
SW1_1A
PS-22E85L-2
LD2_1
RED
R26_1
3K3
+VCC
MUTE
2
1
3
SW2_1A
SW PS-22E85L-2
L-CUT2-OF
L-CUT2-ON INS1-CH2
TRIM2-CH2
TRIM1-CH2
TRIM-CH2
LO-CUT-CH2
VR11_1
O10K
DIR-OUT2
84
U2_1C
4580M
C18_1
100n
C19_1
100n
C20_1
100n
R40_1
15K
VR6_1
W50K
R29_1
4K7
R30_1
4K7
R49_1
4K7
R47_1
10K
R46_1
10K
R45_1
10K
R42_1
100K
R41_1
100K
C21_1
1uF R43_1
8K2
PGND PGND
PGND
PGND
LD3_1
LED-2P
TR1_1
HR
R44_1
82R
1
2
3
4
8
U4_1A
393
5
67
U4_1B
393
R50_1
27K
R51_1
1K
5
67
U3B
4580M
PGND
綠紅
D2_1
4148
D3_1
4148
C22_1
1uF
PGND
D4_1
4148
PGND
+RVCC
TR2_1
7002
R48_1
10K
C23_1
470P
+RVCC
C28_1
47u/25V

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Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW
54of
ALTO L12 VER030712
A3
PCB# L12MN2.PCB
L12MN2CH3(4/5)
R16_2
6K8
VR7_2
W50K
AUX1
R7_2
5K1
5
67
U2_2B
4580M
VR5_2A
10KD
R20_2
12K
C9_2
22P
VR9_2
W50K
C4_2
47u/25V
R14_2
6K8
AUX3
LEVEL
AUX-POST
R8_2
5K1
R9_2
5K1
LEFT-BUS
RIGHT-BUS
PAN
AUX-PRE
21
3
SW7_2A
PS-22E85L
54
6
SW7_2B
PS-22E85L
21
3
SW3_2A
PS-22E85L
54
6
SW3_2B
PS-22E85L
21
3
SW6_2A
PS-22E85L
54
6
SW6_2B
PS-22E85L
54
6
SW4_2B
PS-42E85L
21
3
SW4_2A
PS-42E85L
SUB1
SUB2
R10_2
5K1
R11_2
5K1
AUX1/2 PRE/POST
R5_2
10K
SOLO(PFL)
D1_2
BAS316
LOGIC
LD1_2
YEL
(SOLO)
R23_2
2K2
-VCC
(LOGIC=2.0V or 0.5V)
84
U1_2C
4580M
C17_2
100n
+VCC
-VCC
LOGIC
EQ HI (12K)
C7_2
6.8n(M) VR1_2
B50K
R25_2
5K6
VR4_2
B50K
R24_2
5K6 LO (80Hz)
R4_2
10K
3
21
U2_2A
4580M
R19_2
1M
C6_2
22P
R18_2
3K9
VR2_2
B50K MID (FREQ=100Hz-8K)
C11_2
33n(M) C12_2
33n(M)
C8_2
6.8n(M)
C3_2
47u/25V
C2_2
47u/25V
INS2-CH3 INS2-CH3
3
21
U1_2A
4580M
5
67
U1_2B
4580M
R2_2
10K R3_2 10K
C5_2
22P
C10_2
152(M)
R6_2
5K1
R1_2
3K
VR3_2B
500KC
VR3_2A
500KC
R22_2
6K2
C1_2
682(M)
R21_2
6K2
21
3
SW5_2A
PS-22E85L
54
6
SW5_2B
PS-22E85L
SUB3
SUB4
R12_2
5K1
R13_2
5K1
87
9
SW4_2C
PS-42E85L
11 10
12
SW4_2D
PS-42E85L
AFL-L
AFL-R
R27_2
6K8
R28_2
6K8
VR8_2
W50K
R15_2
6K8
AUX4
AUX-POST
R17_2
6K8
AUX2
VR10_2
W50K
AUX-PRE
5
4
6
SW1_2B
PS-22E85L-2
2
1
3
SW1_2A
PS-22E85L-2
LD2_2
RED
R26_2
3K3
+VCC
MUTE
2
1
3
SW2_2A
SW PS-22E85L-2
L-CUT3-OF
L-CUT3-ON INS1-CH3
TRIM2-CH3
TRIM1-CH3
TRIM-CH3
LO-CUT-CH3
VR11_2
O10K
DIR-OUT3
84
U2_2C
4580M
C18_2
100n
C19_2
100n
C20_2
100n
R40_2
15K
VR6_2
W50K
R29_2
4K7
R30_2
4K7
R49_2
4K7
R47_2
10K
R46_2
10K
R45_2
10K
R41_2
100K
R42_2
100K C21_2
1uF R43_2
8K2
PGND PGND
PGND
PGND
LD3_2
LED-2P
TR1_2
HR
R44_2
82R
1
2
3
4
8
U4_2A
393
5
67
U4_2B
393
R50_2
27K
R51_2
1K
3
21
U3_2A
4580M
PGND
綠紅
D2_2
4148
D3_2
4148
C22_2
1uF
PGND
D4_2
4148
PGND
+RVCC
TR2_2
7002
R48_2
10K
C23_2
470P
+RVCC
C28_2
47u/25V

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Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW
55of
ALTO L12 VER030712
A3
PCB# L12MN2.PCB
L12MN2CH4(5/5)
R16_3
6K8
VR7_3
W50K
AUX1
R7_3
5K1
5
67
U2_3B
4580M
VR5_3A
10KD
R20_3
12K
C9_3
22P
VR9_3
W50K
C4_3
47u/25V
R14_3
6K8
AUX3
LEVEL
AUX-POST
R8_3
5K1
R9_3
5K1
LEFT-BUS
RIGHT-BUS
PAN
AUX-PRE
21
3
SW7_3A
PS-22E85L
54
6
SW7_3B
PS-22E85L
21
3
SW3_3A
PS-22E85L
54
6
SW3_3B
PS-22E85L
21
3
SW6_3A
PS-22E85L
54
6
SW6_3B
PS-22E85L
54
6
SW4_3B
PS-42E85L
21
3
SW4_3A
PS-42E85L
SUB1
SUB2
R10_3
5K1
R11_3
5K1
AUX1/2 PRE/POST
R5_3
10K
SOLO(PFL)
D1_3
BAS316
LOGIC
LD1_3
YEL
(SOLO)
R23_3
2K2
-VCC
(LOGIC=2.0V or 0.5V)
84
U1_3C
4580M
C17_3
100n
+VCC
-VCC
LOGIC
EQ HI (12K)
C7_3
6.8n(M) VR1_3
B50K
R25_3
5K6
VR4_3
B50K
R24_3
5K6
LO (80Hz)
R4_3
10K
3
21
U2_3A
4580M
R19_3
1M
C6_3
22P
R18_3
3K9
VR2_3
B50K
MID (FREQ=100Hz-8K)
C11_3
33n(M) C12_3
33n(M)
C8_3
6.8n(M)
C3_3
47u/25V
C2_3
47u/25V
INS2-CH4 INS2-CH4
5
67
U1_3B
4580M
3
21
U1_3A
4580M
R2_3
10K R3_3
10K
C5_3
22P
C10_3
152(M)
R6_3
5K1
R1_3
3K
VR3_3B
500KC
VR3_3A
500KC
R22_3
6K2
C1_3
682(M)
R21_3
6K2
21
3
SW5_3A
PS-22E85L
54
6
SW5_3B
PS-22E85L
SUB3
SUB4
R12_3
5K1
R13_3
5K1
87
9
SW4_3C
PS-42E85L
11 10
12
SW4_3D
PS-42E85L
AFL-L
AFL-R
R27_3
6K8
R28_3
6K8
VR8_3
W50K
R15_3
6K8
AUX4
AUX-POST
R17_3
6K8
AUX2
VR10_3
W50K
AUX-PRE
5
4
6
SW1_3B
PS-22E85L-2
2
1
3
SW1_3A
PS-22E85L-2
LD2_3
RED
R26_3
3K3
+VCC
MUTE
2
1
3
SW2_3A
SW PS-22E85L-2
L-CUT4-OF
L-CUT4-ON INS1-CH4
TRIM2-CH4
TRIM1-CH4
TRIM-CH4
LO-CUT-CH4
VR11_3
O10K
DIR-OUT4
84
U2_3C
4580M
C18_3
100n
C19_3
100n
C20_3
100n
R40_3
15K
VR6_3
W50K
R29_3
4K7
R30_3
4K7
R49_3
4K7
+RVCC
R47_3
10K
R46_3
10K
R45_3
10K
R41_3
100K
R42_3
100K C21_3
1uF R43_3
8K2
PGND PGND
PGND
PGND
LD3_3
LED-2P
TR1_3
HR
R44_3
82R
1
2
3
4
8
U4_3A
393
5
67
U4_3B
393
R50_3
27K
R51_3
1K
5
67
U3_2B
4580M
PGND
綠紅
D2_3
4148
D3_3
4148
C22_3
1uF
PGND
D4_3
4148
PGND
+RVCC
TR2_3
7002
R48_3
10K
C23_3
470P
C28_3
47u/25V

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File:
Date: Drawn By: Sheet
RevisionModel No:
18-Jun-2003 BOW.
MAIN INPUT STAGE
81of
ALTO L12 VER030531
A4
PCB# L12MN1.PCB
L12MN1
INS-CH11
INS-CH12
INS-CH10
INS-CH9
L12STEREO
L12STEREO.SCH
L12STEREO2
L12STEREO2.SCH
OTHER
OTHER.SCH
AUXRTN
AUXRTN.SCH
AUXSEND
AUXSEND.SCH
CTRMETER
CTRMETER.SCH
L12DSP
L12DSP.SCH
(TO L12PU2-CH5-8)
TRIM2-CH5
TRIM1-CH5
L-CUT5-ON
L-CUT5-OF
INS-CH5-6
PRE-CH5
PRE-CH6
TRIM2-CH7
TRIM1-CH7
L-CUT7-ON
L-CUT7-OF
INS-CH7-8
PRE-CH7
PRE-CH8
PHONE-L
PHONE-R
2TKIN-R
2TKIN-L
MAIN-R-2
MAIN-L-2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
CN4
2.0-14P-B24A
(TO L12PU2-CH9-12) 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
CN5
2.0-15P-B24A
+VCC
-VCC
MONO-LEVEL
DFXOUT-L
DFXOUT-R
AUXRTN1-L
AUXRTN1-R
AUXRTN2-R
AUXRTN2-L
AUXRTN3-R
AUXRTN3-L
AUXRTN4-R
AUXRTN4-L
AUXSEND1
AUXSEND2
AUXSEND3
DFX SEND
(TO L12PU1)
1
2
3
4
5
6
7
8
CN1
2.5-8P
PGND
+VCC-VCCPH PWR +5VD
DGND
(TO L12MN2)
PH PWR
AUX1
AUX3
LEFT-BUS
RIGHT-BUS
SUB1
SUB2
SOLO(PFL)
LOGIC
SUB3
SUB4
AFL-L
AFL-R
AUX4
AUX2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
CN7
2.0-20P-B24A
+VCC
-VCC
MAIN-INS-L
MAIN-INS-R
MAIN-R-2
MAIN-L-2
MAIN-L
MAIN-R
CTRL-R-R
CTRL-R-L
SUB1-L
SUB2-R
SUB3-L
SUB4-R
+VCC
-VCC
(TO L12PU1)
FOOTSW
MAIN-L-3
MAIN-R-3
FOOTSW
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
CN2
2.0-18P-B24A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
CN3
2.0-18P-B24A
EFXRTN-L
EFXRTN-R
PGND

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EQ HI (12KHz)
VR1A
B50K
R44
6K8
VR4A
B50K
R43
6K8
LO(80Hz)
R63
47K
C1
47u/25V
5
67
U1B
4580M
R52
1M
C26
22P
R21
10K
VR2A
B50K
R35
22K MID-LO(500Hz)
R5
1K8
C13
12n(M)
R6
1K8 C41
47n(M)
C33
3.3n(M)
C21
1n(M)
C17
12n(M)
C2
47u/25V
R71
5K1
3
21
U3A
4580M
VR5A
10KD
R96
12K
C45
22P
C4
47u/25V
LEVEL
BAL
R22
8K2
R23
8K2
R72
5K1
5
67
U3B
4580M
VR5B
10KD
R95
12K
C46
22P
C3
47u/25V
LEVEL R25
10K
R24
10K
L12STEREO.Sch
Titel
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File:
Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW.
L12STEREO(CH5-CH8)
82of
ALTO L12 VER030710
A3
R73
12K
R74
12K
LEFT-BUS
RIGHT-BUS
21
3
SW7A
PS-22E85L
54
6
SW7B
PS-22E85L
54
6
SW4B
PS-42E85L
87
9
SW4C
PS-42E85L
AFL-L
AFL-R
R99
20K
R100
20K
R81
5K1
VR7
W50K
AUX2
VR8
W50K
R80
5K1
AUX1
21
3
SW2A
PS-22E85L
54
6
SW2B
PS-22E85L
11 10
12
SW4D
PS-42E85L
AUX1/2 PRE/POST
R26
8K2
SOLO(PFL)
21
3
SW4A
PS-42E85L
D1
BAS316
LOGIC
LD1
YEL (SOLO)
R67
2K2
-VCC
(LOGIC=2.0V or 0.5V)
84
U2C
4580M
84
U3C
4580M
84
U1C
4580M
C53
100N
C54
100N
C55
100N
C56
100N
C57
100N
C58
100N
+VCC
-VCC
PRE-CH5 PRE-CH5
LOGIC
PCB# L12MN1.PCB
3
21
U1A
4580M
R39
220K
C25
22P
R1
220K
R8
1K8
VR3A
B50K
R7
1K8
HI-MID(3KHz)
R59
12K
C37
3.3n(M)
R51
1M
EQ HI (12KHz)
VR1B
B50K
R46
6K8
VR4B
B50K
R45
6K8
LO(80Hz)
R64
47K
C5
47u/25V
5
67
U2B
4580M
R54
1M
C29
22P
R27
10K
VR2B
B50K
R36
22K MID-LO(500Hz)
R9
1K8
C14
12n(M)
R10
1K8 C42
47n(M)
C34
3.3n(M)
C22
1n(M)
C18
12n(M)
C6
47u/25V
PRE-CH6 PRE-CH6
3
21
U2A
4580M
R40
220K
C27
22P
R2
220K
R13
1K8
VR3B
B50K
R11
1K8
HI-MID(3KHz)
R60
12K
C38
3.3n(M)
R53
1M
EQ HI (12KHz)
VR12A
B50K
R50
6K8
VR15A
B50K
R47
6K8
LO(80Hz)
R65
47K
C8
47u/25V
5
67
U6B
4580M
R57
1M
C30
22P
R28
10K
VR13A
B50K
R37
22K MID-LO(500Hz)
R15
1K8
C15
12n(M)
R17
1K8 C43
47n(M)
C35
3.3n(M)
C23
1n(M)
C19
12n(M)
C10
47u/25V
PRE-CH7 PRE-CH7
3
21
U6A
4580M
R41
220K
C28
22P
R3
220K
R14
1K8
VR14A
B50K
R12
1K8
HI-MID(3KHz)
R61
12K
C39
3.3n(M)
R55
1M
EQ HI (12KHz)
VR12B
B50K
R49
6K8
VR15B
B50K
R48
6K8
LO(80Hz)
R66
47K
C9
47u/25V
5
67
U7B
4580M
R58
1M
C32
22P
R29
10K
VR13B
B50K
R38
22K MID-LO(500Hz)
R16
1K8
C16
12n(M)
R20
1K8 C44
47n(M)
C36
3.3n(M)
C24
1n(M)
C20
12n(M)
C11
47u/25V
PRE-CH8 PRE-CH8
3
21
U7A
4580M
R42
220K
C31
22P
R4
220K
R19
1K8
VR14B
B50K
R18
1K8
HI-MID(3KHz)
R62
12K
C40
3.3n(M)
R56
1M
R79
5K1
3
21
U8A
4580M
VR16A
10KD
R97
12K
C47
22P
C7
47u/25V
LEVEL
BAL
R30
8K2
R31
8K2
R85
5K1
5
67
U8B
4580M
VR16B
10KD
R98
12K
C48
22P
C12
47u/25V
LEVEL R33
10K
R32
10K
R86
12K
R87
12K
LEFT-BUS
RIGHT-BUS
21
3
SW14A
PS-22E85L
54
6
SW14B
PS-22E85L
54
6
SW11B
PS-42E85L
87
9
SW11C
PS-42E85L
AFL-L
AFL-R
R101
20K
R102
20K
R94
5K1
VR18
W50K
AUX2
VR19
W50K
R88
5K1
AUX1
21
3
SW9A
PS-22E85L
54
6
SW9B
PS-22E85L
11 10
12
SW11D
PS-42E85L
AUX1/2 PRE/POST
R34
8K2
SOLO(PFL)
21
3
SW11A
PS-42E85L
D2
BAS316
LOGIC
LD2
YEL (SOLO)
R68
2K2
-VCC
(LOGIC=2.0V or 0.5V)
LOGIC
CH5-8 (STEREO)
21
3
SW5A
PS-22E85L
54
6
SW5B
PS-22E85L
SUB1
SUB2
R75
12K
R76
12K
21
3
SW6A
PS-22E85L
SUB3
R77
12K
54
6
SW6B
PS-22E85L
SUB4
R78
12K
R83
5K1
VR9
W50K
AUX4
VR10
W50K
R82
5K1
AUX3
21
3
SW12A
PS-22E85L
54
6
SW12B
PS-22E85L
SUB1
SUB2
R84
12K
R91
12K
21
3
SW13A
PS-22E85L
SUB3
R92
12K
54
6
SW13B
PS-22E85L
SUB4
R93
12K
R90
5K1
VR20
W50K
AUX4
VR21
W50K
R89
5K1
AUX3
5
4
6
SW3B
PS-42E85L
8
7
9
SW3C
PS-42E85L
LD3
RED
R69
3K3
+VCC PGND
MUTE
2
1
3
SW3A
PS-42E85L
2
1
3
SW10A
PS-42E85L
8
7
9SW10C
PS-42E85L
LD4
RED
R70
3K3
+VCC PGND
MUTE
5
4
6
SW10B
PS-42E85L
2
1
3
SW1A
SW PS-22E85L-2
L-CUT5-OF
L-CUT5-ON INS-CH5-6
TRIM2-CH5
TRIM1-CH5
TRIM-CH5LO-CUT-CH5 VR11
O10K
2
1
3
SW8A
SW PS-22E85L-2
L-CUT7-OF
L-CUT7-ON INS-CH7-8
TRIM2-CH7
TRIM1-CH7
TRIM-CH7
LO-CUT-CH7
VR22
O10K
84
U6C
4580M
84
U7C
4580M
84
U8C
4580M
C61
100N
C62
100N
C63
100N
C64
100N
C65
100N
C66
100N
R665
15K
R666
15K
R667
15K
R668
15K
VR6
W50K
R719
4K7
R720
4K7
VR17
W50K
R722
4K7
R721
4K7
R683
4K7
+RVCC
R681
10K
R677
10K
R680
10K
R675
100K
R676
100K C454
1uF R678
8K2
LD39
LED-2P
TR2
HR
R679
82R
1
2
3
4
8U5A
393
5
67
U5B
393
R684
27K
R685
1K
3
21
U4A
4580M
綠紅
D5
BAS316
D6
BAS316
C455
1uF
D7
BAS316
+RVCC
TR9
7002
R682
10K
C456
470P
R694
4K7
R691
10K
R688
10K
R692
10K
R686
100K
R687
100K C457
1uF R689
8K2
LD40
LED-2P
TR8
HR
R690
82R
1
2
3
4
8U9A
393
5
67
U9B
393
R695
27K
R696
1K
5
67
U4B
4580M
綠紅
D8
BAS316
D17
BAS316
C458
1uF
D18
BAS316
+RVCC
TR3
7002
R693
10K
C459
470P
R747
8K2
R748
8K2
R749
8K2
R750
8K2
+RVCC
PGND PGND PGND PGND
PGND
PGND
PGND
PGNDPGNDPGNDPGND
PGND
PGND
PGND
C500
47u/25V
C501
47u/25V
C502
47u/25V
C503
47u/25V

1 2 3 4 5 6 78
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7654321
D
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B
A
L12STEREO2.Sch
Titel
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File:
Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW.
MAIN INPUT STAGE (CH9-CH12)
83of
ALTO L12 VER030710
A3
84
U11C
4580M
84
U12C
4580M
84
U10C
4580M
84
U13C
4580M
C131
100N
C132
100N
C133
100N
C134
100N
C135
100N
C136
100N
C137
100N
C138
100N
+VCC
-VCC
PCB# L12MN1.PCB
EQ HI (12KHz)
VR40A
B50K
R180
6K8
VR43A
B50K
R179
6K8
LO(80Hz)
R197
47K
C104
47u/25V
5
67
U14B
4580M
R188
1M
C113
22P
R160
10K
VR41A
B50K
R169
22K MID-LO(500Hz)
R145
1K8
C108
12n(M)
R146
1K8 C112
47n(M)
C110
3.3n(M)
C106
1n(M)
C107
12n(M)
C122
47u/25V
3
21
U14A
4580M
R173
220K
C109
22P
R135
220K
R149
1K8
VR42A
B50K
R147
1K8
HI-MID(3KHz)
R193
12K
C111
3.3n(M)
R187
1M
EQ HI (12KHz)
VR40B
B50K
R182
6K8
VR43B
B50K
R181
6K8
LO(80Hz)
R198
47K
C105
47u/25V
5
67
U15B
4580M
R189
1M
C121
22P
R161
10K
VR41B
B50K
R170
22K MID-LO(500Hz)
R151
1K8
C116
12n(M)
R152
1K8 C120
47n(M)
C118
3.3n(M)
C114
1n(M)
C115
12n(M)
C123
47u/25V
3
21
U15A
4580M
R174
220K
C117
22P
R136
220K
R150
1K8
VR42B
B50K
R148
1K8
HI-MID(3KHz)
R194
12K
C119
3.3n(M)
R190
1M
R209
5K1
3
21
U17A
4580M
VR39A
10KD
R227
12K
C125
22P
C127
47u/25V
LEVEL
BAL
R162
5K1
R163
5K1
R214
5K1
5
67
U17B
4580M
VR39B
10KD
R228
12K
C126
22P
C128
47u/25V
LEVEL
R165
10K
R164
10K
R215
10K
R216
10K
LEFT-BUS
RIGHT-BUS
21
3
SW26A
PS-22E85L
54
6
SW26B
PS-22E85L
87
9
SW20C
PS-42E85L
54
6
SW20B
PS-42E85L
AFL-L
AFL-R
R231
15K
R232
15K
R224
4K7
VR32
W50K
AUX2
VR33
W50K
R217
4K7
AUX1
21
3
SW16A
PS-22E85L
54
6
SW16B
PS-22E85L 21
3
SW20A
PS-42E85L
AUX1/2 PRE/POST
R166
8K2
SOLO(PFL)
11 10
12
SW20D
PS-42E85L
D4
BAS316
LOGIC
LD6
YEL (SOLO)
R234
2K2
-VCC
(LOGIC=2.0V or 0.5V)
LOGIC
CH9-12 (STEREO)
21
3
SW22A
PS-22E85L
54
6
SW22B
PS-22E85L
SUB1
SUB2
R220
10K
R221
10K
21
3
SW24A
PS-22E85L
SUB3
R222
10K
54
6
SW24B
PS-22E85L
SUB4
R223
10K
R219
4K7
VR34
W50K
AUX4
VR35
W50K
R218
4K7
AUX3
2
1
3
SW18A
PS-42E85L
8
7
9SW18C
PS-42E85L
LD8
RED
R200
3K3
+VCC PGND
MUTE
5
4
6
SW18B
PS-42E85L
84
U14C
4580M
84
U15C
4580M
84
U16C
4580M
C139
100N
C140
100N
C141
100N
C142
100N
C143
100N
C144
100N
INS-CH11
INS-CH12
C98
47u/25V 3
21
U11A
4580M
R131
1K2
C102
22P
R127
1K
C100
47u/25V VR23A
W50K
C99
47u/25V 5
67
U11B
4580M
R132
1K2
C103
22P
R128
1K
C101
47u/25V VR23B
W50K
EQ HI (12KHz)
VR24A
B50K
R176
6K8
VR27A
B50K
R175
6K8
LO(80Hz)
R195
47K
C73
47u/25V
5
67
U12B
4580M
R184
1M
C82
22P
R153
10K
VR25A
B50K
R167
22K MID-LO(500Hz)
R137
1K8
C77
12n(M)
R138
1K8 C81
47n(M)
C79
3.3n(M)
C75
1n(M)
C76
12n(M)
C83
47u/25V
3
21
U12A
4580M
R171
220K
C78
22P
R133
220K
R140
1K8
VR26A
B50K
R139
1K8
HI-MID(3KHz)
R191
12K
C80
3.3n(M)
R183
1M
EQ HI (12KHz)
VR24B
B50K
R178
6K8
VR27B
B50K
R177
6K8
LO(80Hz)
R196
47K
C74
47u/25V
5
67
U13B
4580M
R186
1M
C91
22P
R158
10K
VR25B
B50K
R168
22K MID-LO(500Hz)
R141
1K8
C86
12n(M)
R142
1K8 C90
47n(M)
C88
3.3n(M)
C84
1n(M)
C85
12n(M)
C92
47u/25V
3
21
U13A
4580M
R172
220K
C87
22P
R134
220K
R144
1K8
VR26B
B50K
R143
1K8
HI-MID(3KHz)
R192
12K
C89
3.3n(M)
R185
1M
R201
5K1
3
21
U16A
4580M
VR38A
10KD
R226
12K
C95
22P
C97
47u/25V
LEVEL
BAL
R154
5K1
R159
5K1
R202
5K1
5
67
U16B
4580M
VR38B
10KD
R225
12K
C94
22P
C96
47u/25V
LEVEL
R156
10K
R155
10K
R203
10K
R204
10K
LEFT-BUS
RIGHT-BUS
21
3
SW25A
PS-22E85L
54
6
SW25B
PS-22E85L
87
9
SW19C
PS-42E85L
54
6
SW19B
PS-42E85L
AFL-L
AFL-R
R229
15K
R230
15K
R211
4K7
VR28
W50K
AUX2
VR29
W50K
R210
4K7
AUX1
21
3
SW15A
PS-22E85L
54
6
SW15B
PS-22E85L
21
3
SW19A
PS-42E85L
AUX1/2 PRE/POST
R157
8K2
SOLO(PFL)
11 10
12
SW19D
PS-42E85L
D3
BAS316
LOGIC
LD5
YEL (SOLO)
R233
2K2
-VCC
(LOGIC=2.0V or 0.5V)
LOGIC
21
3
SW21A
PS-22E85L
54
6
SW21B
PS-22E85L
SUB1
SUB2
R205
10K
R206
10K
21
3
SW23A
PS-22E85L
SUB3
R207
10K
54
6
SW23B
PS-22E85L
SUB4
R208
10K
R213
4K7
VR30
W50K
AUX4
VR31
W50K
R212
4K7
AUX3
2
1
3
SW17A
PS-42E85L
8
7
9SW17C
PS-42E85L
LD7
RED
R199
3K3
+VCC PGND
MUTE
5
4
6
SW17B
PS-42E85L
INS-CH9
INS-CH10
C67
47u/25V 3
21
U10A
4580M
R129
1K2
C71
22P
R125
1K
C69
47u/25V VR44A
W50K
C68
47u/25V 5
67
U10B
4580M
R130
1K2
C72
22P
R126
1K
C70
47u/25V VR44B
W50K
84
U17C
4580M
C145
100N
C146
100N
R657
120R
R658
120R
R659
120R
R660
120R
R661
120R
R662
120R
R663
120R
R664
120R
R669
15K
R670
15K
R671
15K
R672
15K
R724
4K7
R723
4K7
VR36
W50K
R705
4K7
R702
10K
R699
20K
R703
10K
R697
100K
R698
100K C460
1uF R700
8K2
LD41
LED-2P
TR4
HR
R701
150R
1
2
3
4
8U18A
393
5
67
U18B
393
R706
27K
R707
1K
3
21
U20A
4580M
綠紅
D19
BAS316
D25
BAS316
C461
1uF
D26
BAS316
+RVCC
TR1
7002
R704
10K
C462
470P
R716
4K7
R713
10K
R710
20K
R714
10K
R708
100K
R709
100K C463
1uF R712
8K2
LD42
LED-2P
TR6
HR
R711
150R
1
2
3
4
8U19A
393
5
67
U19B
393
R717
27K
R718
1K
5
67
U20B
4580M
綠紅
D27
BAS316
D28
BAS316
C464
1uF
D29
BAS316
+RVCC
TR5
7002
R715
10K
C465
470P
R726
4K7
R725
4K7
VR37
W50K
R751
5K1
R752
5K1
R753
5K1
R754
5K1
+RVCC
+RVCC
PGNDPGNDPGNDPGND
PGND
PGND
PGND
PGND
PGND
PGND PGND PGND PGND
PGND
C504
47u/25V
C505
47u/25V
C506
47u/25V
C507
47u/25V

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OTHER.Sch
Titel
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Date: Drawn By: Sheet
RevisionModel No:
1-Oct-2003 BOW.
MAIN INPUT STAGE
84 of
ALTO LM12 VER030710
A3
PCB# L12PU2.PCB
3
21
U34A
4580M
R387
20K
C245
22P
SUB1 C247
47u/25V
5
67
U34B
4580M
R389
18K
C246
22P
VR66
10KD
SUB1
C248
47u/25V R390
10K
R388
5K1
SUB1-L SUB1-L
R392
20K
RIGHT-BUS
LEFT-BUS
R391
20K
R386
510R
3
21
U35A
4580M
R394
20K
C249
22P
SUB2 C251
47u/25V
5
67
U35B
4580M
R396
18K
C250
22P
SUB2
C252
47u/25V R397
10K
SUB2-R SUB2-R
R399
20K
RIGHT-BUS
LEFT-BUS
R398
20K
R393
510R
3
21
U36A
4580M
R401
20K
C253
22P
SUB3 C255
47u/25V
5
67
U36B
4580M
R403
18K
C254
22P
SUB3
C256
47u/25V R404
10K
SUB3-L SUB3-L
R406
20K
RIGHT-BUS
LEFT-BUS
R405
20K
R400
510R
3
21
U37A
4580M
R408
20K
C257
22P
SUB4 C259
47u/25V
5
67
U37B
4580M
R410
18K
C258
22P
SUB4
C260
47u/25V R411
10K
SUB4-R
R413
20K
RIGHT-BUS
LEFT-BUS
R412
20K
R407
510R
SUB4-R
SW37A
PS-22E85L
SW48A
PS-22E85L
SW38A
PS-22E85L
SW49A
PS-22E85L
SW39A
PS-22E85L
SW50A
PS-22E85L
SW40A
PS-22E85L
SW51A
PS-22E85L
3
21
U40A
4580M
R428
20K
C269
22P
LEFT-BUS
RIGHT-BUS
C285
47u/25V
5
67
U41B
BA1458
3
21
U41A
BA1458
3
21
U45A
BA1458
5
67
U45B
BA1458
3
21
U47A
BA1458
R430
10K C273
22P
R436
10K
R434
10K
R432
49K9
C271
22P R446
10K
R450
10K
C281
22P
R452
10K
R448
49K9
C279
22P
R454
10K R456
10K
C283
22P C287
47u/25V
63HZ-L 250HZ-L 1KHZ-L 4KHZ-L
125HZ-L 500HZ-L 2KHZ-L 8KHZ-L
16KHZ-L
EQ-VRL-A EQ-OPL-A 5
67
U43B
BA1458
3
21
U43A
BA1458
R438
10K
R444
10K
C277
22P
R442
10K
R440
49K9
C275
22P
EQ-VRL-B
EQ-OPL-B
EQ-VRL-C
EQ-VRL-A
EQ-VRL-B
EQ-VRL-C
63HZ-L
250HZ-L
1KHZ-L
4KHZ-L
16KHZ-L
3
21
U52A
BA1458
R477
10K
R474
19K6
R475
9K76
R476
1K18
C298
2N2
C297
2N2
3
21
U53A
BA1458
R481
10K
R478
76K8
R479
38K3
R480
4K75
C300
2N2
C299
2N2
3
21
U54A
BA1458
R485
10K
R482
30K1
R483
15K
R484
1K96
C302
22N
C301
22N
3
21
U55A
BA1458
R489
10K
R486
12K1
R487
6K04
R488
787R
C304
0.22uF
C303
0.22uF
3
21
U56A
BA1458
R493
10K
R490
48K7
R491
24K3
R492
3K01
C306
0.22uF
C305
0.22uF
125HZ-L
500HZ-L
2KHZ-L
8KHZ-L
3
21
U48A
BA1458
R461
10K
R458
38K3
R459
19K1
R460
2K43
C290
2N2
C289
2N2
3
21
U49A
BA1458
R465
10K
R462
15K
R463
7K5
R464
976R
C292
22N
C291
22N
3
21
U50A
BA1458
R469
10K
R466
60K4
R467
30K1
R468
3K92
C294
22N
C293
22N
3
21
U51A
BA1458
R473
10K
R470
24K3
R471
12K1
R472
1K54
C296
0.22uF
C295
0.22uF
EQ-OPL-B
MAIN-INS-L
5
67
U40B
4580M
R429
20K
C270
22P
C286
47u/25V
5
67
U42B
BA1458
3
21
U42A
BA1458
3
21
U46A
BA1458
5
67
U46B
BA1458
5
67
U47B
BA1458
R431
10K C274
22P
R437
10K
R435
10K
R433
49K9
C272
22P R447
10K
R451
10K
C282
22P
R453
10K
R449
49K9
C280
22P
R455
10K R457
10K
C284
22P C288
47u/25V
EQ-VRR-A EQ-OPR-A 5
67
U44B
BA1458
3
21
U44A
BA1458
R439
10K
R445
10K
C278
22P
R443
10K
R441
49K9
C276
22P
EQ-VRR-B
EQ-OPR-B
EQ-VRR-C
MAIN-INS-R
63HZ-R 250HZ-R 1KHZ-R 4KHZ-R
125HZ-R 500HZ-R 2KHZ-R 8KHZ-R
16KHZ-R
EQ-VRR-A
EQ-VRR-B
EQ-VRR-C
63HZ-R
250HZ-R
1KHZ-R
4KHZ-R
16KHZ-R
5
67
U52B
BA1458
R513
10K
R510
19K6
R511
9K76
R512
1K18
C316
2N2
C315
2N2
5
67
U53B
BA1458
R517
10K
R514
76K8
R515
38K3
R516
4K75
C318
2N2
C317
2N2
5
67
U54B
BA1458
R521
10K
R518
30K1
R519
15K
R520
1K96
C320
22N
C319
22N
5
67
U55B
BA1458
R525
10K
R522
12K1
R523
6K04
R524
787R
C322
0.22uF
C321
0.22uF
5
67
U56B
BA1458
R529
10K
R526
48K7
R527
24K3
R528
3K01
C324
0.22uF
C323
0.22uF
125HZ-R
500HZ-R
2KHZ-R
8KHZ-R
5
67
U48B
BA1458
R497
10K
R494
38K3
R495
19K1
R496
2K43
C308
2N2
C307
2N2
5
67
U49B
BA1458
R501
10K
R498
15K
R499
7K5
R500
976R
C310
22N
C309
22N
5
67
U50B
BA1458
R505
10K
R502
60K4
R503
30K1
R504
3K92
C312
22N
C311
22N
5
67
U51B
BA1458
R509
10K
R506
24K3
R507
12K1
R508
1K54
C314
0.22uF
C313
0.22uF
EQ-OPR-B
VR57A
W100K
VR58A
W100K
VR60A
W100K
VR59A
W100K
VR61A
W100K
VR62A
W100K
VR64A
W100K
VR63A
W100K
VR65A
W100K
VR57B
W100K
VR58B
W100K
VR60B
W100K
VR59B
W100K
VR61B
W100K
VR62B
W100K
VR64B
W100K
VR63B
W100K
VR65B
W100K
EQ-OPL-A
EQ-OPR-A
9 BAND EQ
SW41A
PS-22E85L
SW41B
PS-22E85L
VR53
10KD
R395
5K1
VR54
10KD
R402
5K1
VR55
10KD R409
5K1
84
U33C
4580M
84
U34C
4580M
C327
100N
C328
100N
C325
100N
C326
100N
84
U35C
4580M
84
U36C
4580M
84
U37C
4580M
84
U38C
4580M
84
U39C
4580M
84
U40C
4580M
84
U41C
4580M
84
U42C
4580M
84
U43C
4580M
84
U44C
4580M
84
U45C
4580M
84
U46C
4580M
84
U47C
4580M
84
U48C
4580M
84
U49C
4580M
84
U50C
4580M
84
U51C
4580M
84
U52C
4580M
84
U53C
4580M
84
U54C
4580M
84
U55C
4580M
84
U56C
4580M
C331
100N
C332
100N
C329
100N
C330
100N
C335
100N
C336
100N
C333
100N
C334
100N
C339
100N
C340
100N
C337
100N
C338
100N
C343
100N
C344
100N
C341
100N
C342
100N
C347
100N
C348
100N
C345
100N
C346
100N
C351
100N
C352
100N
C349
100N
C350
100N
C355
100N
C356
100N
C353
100N
C354
100N
C359
100N
C360
100N
C357
100N
C358
100N
C363
100N
C364
100N
C361
100N
C362
100N
C367
100N
C368
100N
C365
100N
C366
100N
C371
100N
C372
100N
C369
100N
C370
100N
+VCC
-VCC
3
21
U38A
4580M
3
21
U39A
4580M
R416
18K
C261
22P
R414
5K1
VR56A
10KD
MAIN MIX
VR56B
10KD
R417
18K
C262
22P
R415
5K1
C265
47u/25V
C267
47u/25V
R424
10K
R425
10K
MAIN MIX
LEFT
RIGHT
MAIN-L-3
MAIN-R-3
(BALANCED)
5
67
U38B
4580M
C263
22P
C266
47u/25V
R422
5K1
R426
10K
R418
5K1
MAIN OUT
LEFT
RIGHT
MAIN-L-2
5
67
U39B
4580M
C264
22P
C268
47u/25V
R423
5K1
R427
10K
R419
5K1
MAIN-R-2
MAIN-R-3
MAIN-R-2
MAIN-L-2
MAIN-L-3
MAIN-L
MAIN-R
R420
22K
R421
22K
MONO-LEVEL
C240
47u/25V
R379
20K
5
67
U33B
4580M
R381
22K
C242
22P
C244
47u/25V
R383
10K
R385
18K
C239
47u/25V
R378
20K
3
21
U33A
4580M
R380
22K
C241
22P
C243
47u/25V
R382
10K
R384
18K LEFT-BUS
RIGHT-BUS
2TK TO MIX
C237
100P
C238
100P
2TKIN-L
2TKIN-R
SW36A
PS-22E85L
SW36B
PS-22E85L
2TKIN-L
2TKIN-R
2TK TO CR-L
2TK TO CR-R
R673
20K
R674
20K
R728
15K
R727
15K
3
21
U78A
4580M
R731
10K
C468
22P
R729
10K
5
67
U78B
4580M
R732
10K
C469
22P
R730
10K
84
U78C
4580M
C49
100N
C50
100N
U45 U46 U47 U48 U49 U50 U51 U52 U53 U54 U55 U56 U57 U58 U59 U60 U61 U62 U63 U64 U65 U66 U67 U68 U69

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AUXRTN.Sch
Titel
Size
File:
Date: Drawn By: Sheet
RevisionModel No:
12-Jul-2003 BOW.
MAIN INPUT STAGE (AUXRTN)
85of
ALTO L12 VER030710
A3
PCB# S16MN1.PCB
R298
56K
R329
3K6
C174
100P R297
56K
R330
3K6
VR52B
W50K
VR52A
W50K
3
21
U29A
4580M
5
67
U29B
4580M
R343
36K
C181
22P
C183
47u/25V
R351
20K
R344
36K
C182
22P
C184
47u/25V
R352
20K
AUX RETURN 1
LEFT-BUS
RIGHT-BUS
R306
56K
R335
3K6
R308
56K
R336
3K6
VR45B
W50K
VR45A
W50K
3
21
U30A
4580M
5
67
U30B
4580M
R345
36K
C193
22P
C195
47u/25V
R347
36K
C194
22P
C196
47u/25V
AUX RETURN 2
LEFT-BUS
RIGHT-BUS
C173
100P
C185
100P
C186
100P
AUXRTN1-L
AUXRTN1-R
AUXRTN2-R
AUXRTN2-L
AUXRTN1-L
AUXRTN1-R
AUXRTN2-R
AUXRTN2-L
AUXRTN.SCH
C175
47u/25V
C176
47u/25V
C187
47u/25V
C188
47u/25V
R326
5K1
R325
5K1
R328
5K1
R327
5K1 21
3
SW31A
PS-42E85L
R299
10K
SOLO(PFL)
87
9
SW31C
PS-42E85L
54
6
SW31B
PS-42E85L
AFL-L
AFL-R
R367
27K
R368
27K
R353
4K7
AUX1
VR48
W50K
R332
5K1
R331
5K1
R334
5K1
R333
5K1
R309
10K
R369
27K
R370
27K
R357
4K7
AUX2
VR49
W50K
R354
20K
R355
20K
LEFT-BUS
RIGHT-BUS
LEFT-BUS
RIGHT-BUS
R307
56K
R338
3K6
R320
56K
R339
3K6
VR46B
W50K
VR46A
W50K
3
21
U31A
4580M
5
67
U31B
4580M
R346
36K
C205
22P
C207
47u/25V
R349
36K
C206
22P
C208
47u/25V
AUX RETURN 3
C197
100P
C198
100P
AUXRTN3-R
AUXRTN3-L
AUXRTN3-R
AUXRTN3-L
C199
47u/25V
C200
47u/25V
R315
5K1
R314
5K1
R374
27K
R371
27K
R316
10K
R356
20K
R361
20K
LEFT-BUS
RIGHT-BUS
LEFT-BUS
RIGHT-BUS
SW32A
PS-22E85L
SW32B
PS-22E85L
R376
10K
R377
10K
CTRL/L
CTRL/R
R319
100K
R340
3K6
R324
100K
R342
3K6
VR47B
W50K
VR47A
W50K
3
21
U32A
4580M
5
67
U32B
4580M
R348
36K
C217
22P
C219
47u/25V
R350
36K
C218
22P
C220
47u/25V
AUX RETURN 4
C209
100P
C210
100P
AUXRTN4-R
AUXRTN4-L
AUXRTN4-R
AUXRTN4-L
C211
47u/25V
C212
47u/25V
R318
5K1
R323
5K1
R358
20K
R359
20K
LEFT-BUS
RIGHT-BUS
21
3
SW35A
PS-22E85L
54
6
SW35B
PS-22E85L
21
3
SW33A
PS-22E85L
54
6
SW33B
PS-22E85L
SUB1
SUB2
R360
20K
R362
20K
21
3
SW34A
PS-22E85L
SUB3
R363
20K
54
6
SW34B
PS-22E85L
SUB4
R364
20K
R317
10K
R337
5K1
R341
5K1
R365
4K7
AUX1
VR50
W50K
R366
4K7
AUX2
VR51
W50K
TO AUX SEND2
TO AUX SEND1
MAIN MIX / CTRL/R
R372
30K
R373
30K
DFX TO MONITOR
DFX TO MONITOR
AUX2
AUX1
11 10
12
SW31D
PS-42E85L D13 BAS316
LOGIC
(SOLO)
(LOGIC=2.0V or 0.5V)
LOGIC
LD9
RED
R375
2K2
-VCC
84
U29C
4580M
C229
100N
C230
100N
84
U30C
4580M
84
U31C
4580M
84
U32C
4580M
C231
100N
C232
100N
C233
100N
C234
100N
C235
100N
C236
100N
84
U25C
4580M
C221
100N
C222
100N
84
U26C
4580M
84
U27C
4580M
84
U28C
4580M
C223
100N
C224
100N
C225
100N
C226
100N
C227
100N
C228
100N
+VCC
-VCC
C180
47u/25V
C179
47u/25V
R293
10K
R294
10K
3
21
U25A
4580M
5
67
U25B
4580M
C177
22P
C178
22P
R295
5K1
R296
5K1
C191
47u/25V
C192
47u/25V
R301
10K
R300
10K
3
21
U26A
4580M
5
67
U26B
4580M
C189
22P
C190
22P
R303
5K1
R304
5K1
C203
47u/25V
C204
47u/25V
R302
10K
R310
10K
3
21
U27A
4580M
5
67
U27B
4580M
C201
22P
C202
22P
R305
5K1
R312
5K1
C215
47u/25V
C216
47u/25V
R311
10K
R321
10K
3
21
U28A
4580M
5
67
U28B
4580M
C213
22P
C214
22P
R313
15K
R322
15K
C498
47u/25V
C497
47u/25V
R740
15K
R739
15K
C496
47u/25V
C495
47u/25V
C494
47u/25V
C493
47u/25V
R738
15K
R737
15K
R736
15K
R735
15K
C492
47u/25V
C491
47u/25V
R734
15K
R733
15K

12345678
A
B
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8
7654321
D
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A
3
21
U21A
4580M
R261
36K
C149
22P
AUX1 C153
47u/25V
5
67
U21B
4580M
R262
36K
C157
22P
VR69
W50K
AUX1 SEND
C161
47u/25V R270
10K
R269
6K2
AUXSEND1 AUXSEND1
21
3
SW27A
PS-42E85L
R281
8K2
SOLO(PFL)
87
9
SW27C
PS-42E85L
54
6
SW27B
PS-42E85L
AFL-L
AFL-R
R282
27K
R283
27K
11 10
12
SW27D
PS-42E85L D9 BAS316
LOGIC
(SOLO)
(LOGIC=2.0V or 0.5V)
LOGIC
R257
510R
3
21
U22A
4580M
R263
36K
C150
22P
AUX2 C154
47u/25V
5
67
U22B
4580M
R264
36K
C158
22P
VR70
W50K
AUX2 SEND
C162
47u/25V R272
10K
R271
6K2
AUXSEND2 AUXSEND2
21
3
SW28A
PS-42E85L
R284
8K2
SOLO(PFL)
87
9
SW28C
PS-42E85L
54
6
SW28B
PS-42E85L
AFL-L
AFL-R
R285
27K
R286
27K
11 10
12
SW28D
PS-42E85L D10 BAS316
LOGIC
(SOLO)
(LOGIC=2.0V or 0.5V)
LOGIC
R258
510R
3
21
U23A
4580M
R265
36K
C151
22P
AUX3 C155
47u/25V
5
67
U23B
4580M
R266
36K
C159
22P
VR71
W50K
AUX3 SEND
C163
47u/25V R274
10K
R273
6K2
AUXSEND3 AUXSEND3
21
3
SW29A
PS-42E85L
R288
8K2
SOLO(PFL)
87
9
SW29C
PS-42E85L
54
6
SW29B
PS-42E85L
AFL-L
AFL-R
R287
27K
R289
27K
11 10
12
SW29D
PS-42E85L D11 BAS316
LOGIC
(SOLO)
(LOGIC=2.0V or 0.5V)
LOGIC
R259
510R
3
21
U24A
4580M
R267
36K
C152
22P
AUX4 C156
47u/25V
5
67
U24B
4580M
R268
36K
C160
22P
VR72
W50K
AUX4 SEND
C164
47u/25V R276
10K
R275
6K2
DFX SEND
21
3
SW30A
PS-42E85L
R291
8K2
SOLO(PFL)
87
9
SW30C
PS-42E85L
54
6
SW30B
PS-42E85L
AFL-L
AFL-R
R290
27K
R292
27K
11 10
12
SW30D
PS-42E85L D12 BAS316
LOGIC
(SOLO)
(LOGIC=2.0V or 0.5V)
LOGIC
R260
510R
DFX SEND
AUXSEND.SCH
Titel
Size
File:
Date: Drawn By: Sheet
RevisionModel No:
18-Jun-2003 BOW.
MAIN INPUT STAGE (AUXSEND)
86of
ALTO L12 VER020530
A3
PCB# L12MN1.PCB
84
U21C
4580M
C165
100N
C166
100N
84
U22C
4580M
84
U23C
4580M
84
U24C
4580M
C167
100N
C168
100N
C169
100N
C170
100N
C171
100N
C172
100N
+VCC
-VCC
AUXSEND