Yamaha Mx12.6 Service Manual

MX12/6
MX20/6
1
SERVICE MANUAL
PA011541
MX12/6  20001210-69800
MX20/6  20001210-99800  1.419K-7721 K          Printed in Japan 2000.12
HAMAMATSU, JAPAN
 CONTENTS
This document is printed on chlorine free (ECF) paper with soy ink.
SPECIFICATIONS ................................................ 3/5
DIMENSIONS ............................................................ 6
PANEL LAYOUT .................................... 7
BLOCK & LEVEL DIAGRAM .......................................................10...

MX12/6
MX20/6
2 2
IMPOR TANT NOTICE
This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has been assumed
that basic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and under-
stood by the users, and have therefore not been restated.
WARNING :Failure to follow appropriate service and safety procedures when servicing this product may result in per-
sonal injury, destruction of expensive components and...

MX12/6
MX20/6
3
SPECIFICATIONS
Frequency response20Hz—20kHz +1dB, -3dB     @+4dB, 600ohms (Input Gain control at minimum level)
Total harmonic distortion

MX12/6
MX20/6
4
 Input Specifications
Input Gain Input NominalInput level
Connector typeconnectors Control impedance impedance
Sensitivity *1 Nominal Max. before clipping
MIC INPUT-60
5k ohms50-600ohms
 mics-80 dB (0.078mV) -60 dB (0.775mV) -40 dB (7.75mV)
XLR-3-31 type *2(1-n *5)
-16 -36 dB (12.3mV) -16 dB (123mV) +4 dB (1.23V)
LINE INPUT-34
50k ohms 600ohms lines-54 dB (1.55mV) -34 dB (15.5mV) -14 dB (155mV)
Phone jack (TRS) *2(1-n *5)
+10 -10 dB (245mV) +10 dB (2.45V) +30 dB (24.5V)
ST INPUT-34
10k...

MX12/6
MX20/6
5 

MX12/6
MX20/6
6
Units: mm
DIMENSIONS
35
658
58835
11835 35
< MX20/6 >
< MX12/6 >
46854.6
17.6
438
368
268
384
118
46 

MX12/6
MX20/6
7
1
2
3
4
5
6
7
8
9
PANEL LAYOUT
Channels
1-8 (MX12/6)
1-16 (MX20/6)
(Monaural)Channels
9-12 (MX12/6)
17-20 (MX20/6)
(Stereo)
1
2
3
6
7
8
9
8
44
55
GAIN Control
PEAK Indicator
Equalizer
AUX1, AUX2 Controls
POST Switch
EFFECT Control
PAN Control (MX12/6:CH1-8, MX20/6:CH1-16)
BAL Control (MX12/6:CH9-12, MX20/6:CH17-20)
GROUP, ST Select Switches
Channel Fader
 
Channel Control Section 

MX12/6
MX20/6
8
1314
12
1011
8
2
1
43
6
7
5
9
1
2
3
4
5
6
7
8
9
10
11
12
13
14
ST Master Fader
MONO Control
GROUP 1-4 Faders
TO ST Switch
SEND
RETURN
DIGITAL EFFECT
TAPE IN Control
ST GRAPHIC EQUALIZER
C-R/PHONES Output and Meter Select Switch
C-R/PHONES Control
LEVEL Meter
POWER Indicator
LAMP Connector
 
Master Control Section 

MX12/6
MX20/6
9
1245
3
765431
2
8
 
Connector Section
 
Rear Panel
1
2
3
4
5INPUT Jacks (MX12/6:CH1-8, MX20/6:CH1-16)
INPUT Jacks (MX12/6:CH9-12, MX20/6:CH17-20)
ST OUT (L, R) Jacks
MONO OUT Jack
C-R/PHONES Jack
1
2
3
4
5
6
7
8INSERT I/O Jack (MX12/6:CH1-4, MX20/6:CH1-8)
PHANTOM +48V Switch
SEND Jack
RETURN L (MONO), R Jacks
GROUP OUT (1-4) Jacks
TAPE IN (L, R) Jacks
REC OUT (L, R) Jacks
POWER Switch 

MX12/6
MX20/6
10
BLOCK & LEVEL DIAGRAM
+30dB
+20dB
+10dB
0dB
-10dB
-20dB
-30dB
-40dB
-50dB
-60dB
CH INPUT LINE IN
GAIN Min.[+10dB]
CH INPUT MIC IN
GAIN Min.[-16dB]
CH INPUT LINE IN
GAIN Max.[-34dB]
CH INPUT MIC IN
GAIN Max.[-60dB]ST INPUT
GAIN Min.[+10dB] ST INPUT
GAIN Min.[+10dB]
ST INPUT
GAIN Max.[-34dB]Max. Before Clip
INSERT I/O [0dB]Max. Before Clip
TAPE IN [-10dBV]
FaderRETURN [+4dB]
CH & ST INPUT to GROUP/STEREO [0dB]
RETURN to AUX/STEREO [-2dB]
CH & ST INPUT to AUX/EFFECT [-6dB]
TAPE IN & DSP to...