Yamaha Mx12.6 Service Manual

   
 
 
to IN8-CN404
(MX20/6 only)to DCJK1/2
-CN101 or CN108to DCJK2/2-CN302
GAIN
HIGH
MID
LOW
AUX1
AUX2
EFFECT
1-2
3-4
ST
1 2 3 4 5 6 7 8 9/10DIGITAL EFFECT
PAN
POST POST POST POST POST POST POST POST POST POST
BALST GRAPHIC EQUALIZER
11/12 to DCJK2/2-CN301 to DCJK1/2-CN106 (MX12/6 only)
Component side
Component side Component side MAIN2/4 Circuit Board
MAIN1/4 Circuit Board
MAIN3/4 Circuit Board
to DCJK1/2-CN105
Component side MAIN4/4 Circuit Board
CIRCUIT BOARDS
3NA-V6258102
C
C
C
C
(MX20/6)...

(MX12/6 only)
MAIN2/4 Circuit Board
MAIN2/4 Circuit Board
MAIN3/4 Circuit Board
MAIN4/4 Circuit Board
Pattern sidePattern side Pattern side
Pattern side MX12/6
MX20/6
22 

23 MX12/6
MX20/6
to ACto Power Switch CN105: to MAIN4/4-CN305
to MAIN3/4
-CN306 CN103:
CN104:
CN109:
to MAIN1/4-CN201 to MAIN1/4-CN202
to Power Transformer
CN107:to MAIN1/4-CN207(MX12/6)
to IN8 1/2-CN403(MX20/6)CN108:to MAIN1/4-CN207(MX12/6)
to IN8 1/2-CN403(MX20/6)
L REC OUT TAPEIN 1 2 3 4 R L(MONO) EFFECT AUX2 SEND
AUX1
R
RETURN
ROUP OUT
CIRCUIT BOARDS
 
DCJK1/2 Circuit Board
Component side
Component side 
DCJK2/2 Circuit Board
3NA: V626340  1 

MX12/6
MX20/6
24
A
A
to DCJK1/2
-CN107
GAIN HIGH MI
D
34 567 8 2INSERT I/O
1345678 2INSERT I/O
1
34 5 6 7 8 2 1
MICLINE
 
IN8 1/2 Circuit Board
  (MX20/6 only) 
IN8 2/2 Circuit Board
  (MX20/6 only) 

25 MX12/6
MX20/6
A
A
to MAIN1/4-CN208
HIGH MID AUX1 AUX2LOW EFFECT
PANBAL
Component side3NA: V626330  2 

MX12/6
MX20/6
26
A
A 
IN2/1 Circuit Board 

27 MX12/6
MX20/6
A
A
Pattern side Pattern side
 
IN2/2 Circuit Board 

MX12/6
MX20/6
28
INSPECTIONS
1. Preparation
Set the operation elements of the equipment as described below unless otherwise specified.
1-1. Initial conditions
Power supply voltage within AC100V ± 2%
Environment conditions Temperature: 25 ± 5°C Humidity: 65 ± 5%
1-2. Panel operation elements
Channel input section (CH1 to CH8)
GAIN control: MAX (-60dB)
HI, MID, LO EQ level: Center
AUX1, AUX2, EFFECT level control: MAX
AUX2 POST switch: OFF (PRE)
PAN control: L (turned counterclockwise fully)
1-2, 3-4, ST...

29 MX12/6
MX20/6
*1 Measure with the PAN control set at the center position. For others, turn the PAN control counterclockwise fully for the odd
number OUT of L and GROUP and turn it clockwise fully for the even number OUT of R and GROUP. Also, for MONO OUT,
check both when the PAN control is turned clockwise fully and counterclockwise fully.
*2 Only CH1 can be checked.
*1 Measure with the BAL control set at the center position. For others, turn the BAL control counterclockwise fully for the odd
number...

MX12/6
MX20/6
302-2. Frequency response
In the state checked in 2-1 above, check the frequency response measured at 20Hz and 20kHz of each input/output is within
the range of 0+1/-2.5 dB of the 1kHz frequency as reference value (0dB). However, the level at 20Hz when the GAIN volume is
maximum should be within the range of 0+1.0/-4.5 dB of the 1kHz frequency as reference value (0dB).
For Table 1, check at every OUT for CH 1 only, and at ST L OUT only for CH 2 and other channels.
For ÒL/MONOÓ of Table 4,...