Yamaha Mla8 Building instructions

SERVICE MANUAL

200406**-73500

■ CONTENTS（目次）

SPECIFICATION（総合仕様）........................................................... 3

DIMENSIONS（寸法図）................................................................... 4

PANEL LAYOUT（パネルレイアウト）.............................................. 5

UNIT LAYOUT（ユニットレイアウト）.............................................. 6

BLOCK DIAGRAM（ブロックダイアグラム）.................................. 7

WIRING（配線図）.............................................................................. 8

DISASSEMBLY PROCEDURE（分解手順）................................. 10

IC BLOCK DIAGRAM（ICブロック図）......................................... 13

CIRCUIT BOARDS（シート基板図）.............................................. 14

INSPECTION（検査）................................................................ 23/25

PARTS LIST

OVERALL CIRCUIT DIAGRAM（総回路図）

MIC LINE AMPLIFIER

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MLA8

2

IMPORTANT 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 understood 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 personal injury,

destruction of expensive components, and failure of the product to perform as specified. For these reasons, we

advise all Yamaha product owners that all service required should be performed by an authorized Yamaha Retailer or

the appointed service representative.

IMPORTANT: The presentation or sale of this manual to any individual or firm does not constitute authorization, certification or

recognition of any applicable technical capabilities, or establish a principle-agent relationship of any form.

The data provided is believed to be accurate and applicable to the unit(s) indicated on the cover. The research, engineering, and

service departments of Yamaha are continually striving to improve Yamaha products. Modifications are, therefore, inevitable and

changes in specification are subject to change without notice or obligation to retrofit. Should any discrepancy appear to exist, please

contact the distributor's Service Division.

WARNING: Static discharges can destroy expensive components. Discharge any static electricity your body may have

accumulated by grounding yourself to the ground bus in the unit (heavy gauge black wires connect to this bus).

IMPORTANT: Turn the unit OFF during disassembly and part replacement. Recheck all work before you apply power to the unit.

WARNING: CHEMICAL CONTENT NOTICE!

The solder used in the production of this product contains LEAD.In addition, other electrical/electronic and/or plastic (where applicable)

components may also contain traces of chemicals found by the California Health and Welfare Agency (and possibly other entities) to cause

cancer and/or birth defects or other reproductive harm.

DO NOT PLACE SOLDER, ELECTRICAL/ELECTRONIC OR PLASTIC COMPONENTS INYOUR MOUTH FOR ANY REASON WHAT-

SOEVER!

Avoid prolonged, unprotected contact between solder and your skin!When soldering, do not inhale solder fumes or expose eyes to solder/

flux vapor!

If you come in contact with solder or components located inside the enclosure of this product, wash your hands before handling food.

■ WARNING (安全上の注意)

Components having special characteristics are marked and must be replaced with parts having specification equal to those originally installed.

印の部品は、安全を維持するために重要な部品です。交換をする場合は、安全のため必ず指定の部品をご使用下さい。

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MLA8

■ SPECIFICATIONS（総合仕様）

Electrical Characteristics

0 dBu is referenced to 0.775 V rms.

General Speciﬁcations

Conditions MIN TYP MAX UNIT

Total Harmonic Distortion (THD+N)

20 Hz - 20 k Hz @ +14 dBu, 10 k ohms,

GAIN Maximum 0.1 %

20 Hz - 20 k Hz @ +14 dBu, 10 k ohms,

GAIN Minimum 0.01 %

Frequency Response

20 Hz - 20 k Hz @ +4 dBu, 10 k ohms,

GAIN Maximum –10 0.5 dB

20 Hz - 20 k Hz @ +4 dBu, 10 k ohms,

GAIN Minimum –0.5 0 0.5 dB

Hum & Noise (20 Hz - 20 k Hz)

PAD OFF, GAIN Maximum

( Sensitivity = –60 dBu ) –128

(68 dB S/N) dBu

PAD ON , GAIN Maximum

( Sensitivity = –34 dBu ) –99

(65 dB S/N) dBu

Rs=150 ohms PAD OFF, GAIN Minimum

( Sensitivity = –16 dBu ) –108

(92 dB S/N) dBu

Hum & Noise are measured with a 6 dB/octave

ﬁlter @12.7 k Hz; equivalent to a 20 k Hz ﬁlter

with inﬁnite dB/octave attenuation.

PAD ON , GAIN Minimum

( Sensitivity = +10 dBu ) –82

(92 dB S/N) dBu

Maximum Voltage Gain CH IN to CH OUT 64 dB

Crosstalk

Adjacent Inputs @ 1 k Hz –90 dB

PAD ON,

GAIN Minimum @ 10 k Hz –70 dB

CH INPUT GAIN control variable 44 dB

CH INPUT PAD switch 26 dB

CH High Pass Filter 80 Hz, 12 dB/octave

Turn over /roll-off frequency of shelving : 3 dB below maximum variable level.

Phantom Power +48 V DC is applied to balanced inputs for powering condenser microphones via 6.8 k ohms

current-limiting/isolation resistors.

CH PEAK LED One red LED per channel. Comes on when post – GAIN signal level reaches +17 dBu.

CH SIGNAL LED One green LED per channel. Comes on when post – GAIN signal level reaches -10 dBu.

Included Accessories

Power Supply Cord, Euroblock Connectors ( 3P x 8 ), Rubber Feet ( x 4 ), Owner's Manual

Power Consumption 25 W

Dimensions (W x H x D) 480 mm x 44 mm x 375.5 mm

Weight 4.7 kg

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MLA8

4

Iuput Characteristics

*1: 0 dBu is referenced to 0.775 Vrms.

Output Characteristics

*1: 0 dBu is referenced to 0.775 Vrms.

D-sub 25pin Assignment Table

PAD Gain Actual Load

Impedance For Use With

Nominal Input Level *1 Connector In

Ampliﬁer unit

Nominal Max. before Clip

0–60

3 k ohms 50 –600 ohms Mics

600 ohms Lines

–60 dBu

(0.775 mV) –40 dBu

(7.75 mV)

XLR-3-31type

(balanced)

26 –34 dBu

(15.5 mV) –14 dBu

(155 mV)

0–16

–16 dBu

(123 mV) +4 dBu

(1.23 V)

26 +10 dBu

(2.45 V) +30 dBu

(24.5 V)

Actual Source

Impedance For Use With

Nominal Output Level *1 Connector In

Ampliﬁer unit

Nominal Max. before Clip

150 ohms 10 k ohms Lines +4 dBu

(1.23 V) +24 dBu

(12.3 V)

Euroblock connectors

(balanced)

D-SUB 25P

female connector

(balanced)

Signal Output Ch Open GND

12345678

Pin Hot 24 10 21 7 18 4 15 1 2, 5, 8, 11, 16,

19, 22, 25

12 23 9 20 6 17 3 14 13

Cold

25 14

13 1

439

430

375.5

353.5

17

348

43

51 220

65 350

480

44

45

22

423

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

1

MIC LINE AMPLIFIER

POWER

ON / OFF

26dB

*

Unit（単位）：m

m

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

2

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

3

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

4

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

5

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

6

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

7

26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

8

26dB

*When the included rubber feet are attached.

（付属のゴム脚取り付け時）

■ DIMENSIONS（寸法図）

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MLA8

■ PANEL LAYOUT（パネルレイアウト）

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POWERスイッチ/インジケーター

[80]ボタン

[26dB]ボタン

[+48V]スイッチ

PEAKインジケーター

SIGNALインジケーター

GAINコントロール

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POWER switch and indicator

[ 80 ] buttons

[26dB] buttons

[+48V] switches

PEAK indicators

SIGNAL indicators

GAIN controls

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!0

AC IN connector

INPUT 1-8 connectors

OUTPUT connectors

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!0

ACIN端子

INPUT1〜8端子

OUTPUT端子

-16

+10 -34

-60

GAIN -16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

SIGNAL

PEAK

OFF ON

+48V

8080

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

12345678

MIC LINE AMPLIFIER

POWER

ON / OFF

26dB 26dB26dB26dB26dB26dB26dB26dB

-16

+10 -34

-60

GAIN

SIGNAL

PEAK

OFF ON

+48V

80

26dB

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1234

5678

INPUT

123

4567

8

GG

ANALOG

OUTPUT

+4dBu

OUTPUT +4dBu

AC IN

!0

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+—

G

Front Panel（フロントパネル）

Rear Panel（リアパネル）

Euroblock Connectors（ユーロブロック端子）

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MLA8

6

■ UNIT LAYOUT（ユニットレイアウト）

Top View（上側より）

Front panel (フロントパネル)

Power Transformer

(電源トランス)

AC INLET

(ACインレット)

AC INLET

(ACインレット)

Power Transformer

(電源トランス)

Front panel (フロントパネル)

HAJK 1/4

HAJK 3/4HAJK 2/4

IN

PS 2/2

PS 1/2

HAJK 4/4

Bottom Shassis Assembly

(ボトムシャーシAss'y)

Bottom Shassis Assembly

(ボトムシャーシAss'y)

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MLA8

■ BLOCK DIAGRAM（ブロックダイアグラム）

IN

28CA1-8830823

IC101

SW102

IC102

SP101

CN114

LD101

PEAK

SIGNAL

LD102

VR101

SW101

SW501

JK101

CN102

CN101

3P

9P

3P

7

151

2

5P

CN107

CN101

CN102

CN103

CN108

CN112

CN110

CN113

CN111

HAJK 3/4

CH1-4

CH5-8

CH2-4

CH5-8

CH2

CH1

CH2

CH8

CH7

AC INLET

CN104

SW101

POWER

F101

FUSE

CN105 3P

4P

TRANSFORMER

CN101

PS 2/2

T100

PS 1/2

CN102

CN103

IC101

+15V

-15V

IC102

+12V

IC102

+15V

-15V

+15V IC104

+48V

-15V HAJK 2/4

HAJK 1/4

CN109

CN105

3P

CN807

CN101

CN801

CN802

CN103

IN

CN102

PEAK

SIGNAL

7

5

1

3P

IC101

CN103

+15V

9P-B

-15V

+12V

+15V

+12V

+15V

+12V

+15V

+12V

+48V

+15V

+12V

CN703

CN708

IN

HAJK 4/4

CN106

CN104

+12V

LD101

POWER

SP701

JK801

3P

9P

9P 3P

+15V

-15V

CH7

CH8

12P

12P-B 12P

12P-B

6P-B

6P 9P

2P-B

2P

5P

2

8

+15V

-15V

4

+15V

8

-15V

4

8

+15V

-15V

4

31

67

8

+15V

IC101

-15V

4

IC101 SW102

31

LD101

LD102

8

+15V

4

-15V

8

+15V

4

-15V

2

3

1

2

3

+12V

5P

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MLA8

8

■ WIRING（配線図）

Power Transformer

PS 1/2

PS 2/2

HAJK 2/4

HAJK 3/4

HAJK 1/4

HAJK 4/4

IN

Power Transformer

8

10

11

9

5

4

3

7

6

20

2

1

89

10 11

12

13

14

15

16

17

18

19

2IN

3IN

4IN

5IN

6IN

7IN

8

1

21 AC INLET

1

13 14 15 16 17 18 19

29

22 30

23 31

24 32

25 33

26 34

27 35

28 36

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MLA8

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!0

!1

!2

!3

!4

!5

!6

!7

!8

!9

@0

@1

@2

@3

@4

@5

@6

@7

@8

@9

#0

#1

#2

#3

#4

#5

#6

(AC INLET)

PS 2/2-CN105

(Power Transformer)

PS 1/2-CN103

PS 1/2-CN102

HAJK 2/4-CN110

HAJK 2/4-CN111

HAJK 2/4-CN108

HAJK 2/4-CN308

HAJK 2/4-CN508

HAJK 2/4-CN708

HAJK 2/4-CN107

HAJK 2/4-CN207

HAJK 2/4-CN307

HAJK 2/4-CN407

HAJK 2/4-CN507

HAJK 2/4-CN607

HAJK 2/4-CN707

HAJK 2/4-CN807

HAJK 1/4-CN104

HAJK 1/4-CN101

HAJK 1/4-CN201

HAJK 1/4-CN301

HAJK 1/4-CN401

HAJK 1/4-CN501

HAJK 1/4-CN601

HAJK 1/4-CN701

HAJK 1/4-CN801

HAJK 1/4-CN102

HAJK 1/4-CN202

HAJK 1/4-CN302

HAJK 1/4-CN402

HAJK 1/4-CN502

HAJK 1/4-CN602

HAJK 1/4-CN702

HAJK 1/4-CN802

PS 2/2-CN104

(Power Transformer)

PS 1/2-CN101

HAJK 2/4-CN109

HAJK 1/4-CN105

HAJK 3/4-CN112

HAJK 3/4-CN113

HAJK 1/4-CN103

HAJK 1/4-CN303

HAJK 1/4-CN503

HAJK 1/4-CN703

IN-CN101 (1)

IN-CN101 (2)

IN-CN101 (3)

IN-CN101 (4)

IN-CN101 (5)

IN-CN101 (6)

IN-CN101 (7)

IN-CN101 (8)

HAJK 4/4-CN106

IN-CN102 (1)

IN-CN102 (2)

IN-CN102 (3)

IN-CN102 (4)

IN-CN102 (5)

IN-CN102 (6)

IN-CN102 (7)

IN-CN102 (8)

IN-CN103 (1)

IN-CN103 (2)

IN-CN103 (3)

IN-CN103 (4)

IN-CN103 (5)

IN-CN103 (6)

IN-CN103 (7)

IN-CN103 (8)

DESTINATION（配線先）

C (Pin3)

C (Pin6)

C (Pin9)

B (Pin12)

C (Pin3)

C (Pin2)

C (Pin5)

C (Pin9)

C (Pin4)

C (Pin5)

B (Pin6)

B (Pin9)

C (Pin12)

C (Pin3)

B (Pin2)

C (Pin5)

C (Pin9)

No.

--

-

* C: Connector

B: Board-in (Soldering)

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MLA8

10

■ DISASSEMBLY PROCEDURE（分解手順）

1. トップカバー（所要時間:約2分）

1-1. [320]のネジ5本と[325]のネジ4本を外し、[340]

のネジ6本とラックアングルを外して、トップ



 カバーを外します。(Fig.1)

1. Top Cover (time required: about 2 minutes)

1-1 Remove the five (5) screws marked [320], the four

(4) screws marked [325], the angle bracket and the

six (6) screws marked [340]. The top cover can then

be removed. (Fig. 1)

[320]: Bind Head Tapping Screw-S 3.0x6 MFZN2BL

(EP630210) +バインドSタイト

[325]: Flat Head Tapping Screw-S 3.0x6 MFZN2BL

(WD010800) +Sタイト平頭

[340]: Bind Head Tapping Screw-S 4.0x8 MFZN2BL

(VI693100) +バインドSタイト (Fig. 1)

Top Cover

(トップカバー)

Angle Bracket, Rack

(ラックアングル)

[340]

[320]

[325]

2. フロントパネル（所要時間:約3分）

2-1. トップカバーを外します。(1項参照)

2-2. [290]のネジ2本と[300]のネジ1本を外して、フ



 ロントパネルを外します。(Photo. 1, 4)



3. 電源トランス（所要時間:約3分）

3-1. トップカバーを外します。(1項参照)

3-2. [45]のネジ4本を外して、シールドケースを外



 し、電源トランスを抜き出します。

(Photo. 1, 2)



4. ACインレット（所要時間:約3分）

4-1. トップカバーを外します。(1項参照)

4-2. [60]のネジ2本と[390]のネジ1本を外して、AC



 インレットを外します。(Photo.3)

2. Front Panel (time required: about 3 minutes)

2-1 Remove the top cover. (See Procedure 1.)

2-2 Remove the two (2) screws marked [290] and the

screw marked [300]. The front panel can then be

removed. (Photo. 1, 4)

3.

Power Transformer (time required: about 3 minutes)

3-1 Remove the top cover. (See Procedure 1.)

3-2

Remove the four (4) screws marked [45] and the shield

case. The power transformer can then be removed.

(Photo. 1, 2)

4.

AC Inlet (time required: about 3 minutes)

4-1 Remove the top cover. (See Procedure 1.)

4-2

Remove the two (2) screws marked [60] and the screw

marked [390]. The AC inlet can then be removed.

(Photo. 3)

[45]: Bind Head Tapping Screw-S 3.0x6 MFZN2BL (EP630210) +バインドSタイト

[60]: Bind Head Tapping Screw-S 3.0x8 MFZN2BL (EP600530) +バインドSタイト

[290]: Bind Head Tapping Screw-S 3.0x6 MFZN2BL (EP630210) +バインドSタイト

[390]: Bind Head Tapping Screw-S 4.0x8 MFZN2BL (VI693100) +バインドSタイト

(Photo. 1) (Photo. 3)

Power Transformer

(電源トランス)

[45]

Shield case (シールドケース)

Power Transformer

(電源トランス)

(Photo. 2)

AC INLET (ACインレット)

[45]

[290]

[390]

[60]

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11

MLA8

5. PS1/2シート（所要時間:約3分）

5-1. トップカバーを外します。(1項参照)

5-2. [140]のネジ6本を外して、PS1/2シートを外

し

 ます。(Photo. 4)

5.

PS 1/2 Circuit Board (time required: about 3 minutes)

5-1 Remove the top cover. (See Procedure 1.)

5-2 Remove the six (6) screws marked [140]. The PS

1/2 circuit board can then be removed. (Photo. 4)

Front panel (フロントパネル)

Power Transformer

(電源トランス)

[110], [140], [200]: Bind Head Tapping Screw-B 3.0x6 MFZN2BL (EP630210) +バインドSタイト

[300]: Flat Head Tapping Screw-S 3.0x6 MFZN2BL (WD010800) Sタイト平頭

(Photo. 4)

[140]

[110]

[200] [200]

[300]

AC INLET

(ACインレット)

[200]

AC INLET

(ACインレット)

Power Transformer

(電源トランス)

Front panel (フロントパネル) HAJK 1/4

PS 1/2

HAJK 3/4HAJK 2/4 [110]

[110]

IN

PS 2/2

[200]

[300]

6. HAJK1/4シート（所要時間:約4分）

6-1. トップカバーを外します。(1項参照)

6-2. フロントパネルを外します。(2項参照)

6-3. [210]のツマミ8個と[350]のノブ8個外して、



 [A]の六角ナット8個を外し、[200]のネジ4本

を

 外して、HAJK1/4シートを外します。

(Photo.4,5)

7. INシート（所要時間:約4分）

7-1. トップカバーを外します。(1項参照)

7-2. フロントパネルを外します。(2項参照)

7-3. HAJK1/4シートを外します。(6項参照)

7-4. カードホルダのフックを引きながら、INシー



 トを取り外します。(Photo.6,7)

6.

HAJK 1/4 Circuit Board (time required: about 4 minutes)

6-1. Remove the top cover. (See Procedure 1.)

6-2.

Remove the front panel. (See Procedure 2.)

6-3. Remove the eight (8) knobs marked [210], the eight

(8) knobs marked [350], the eight (8) hexgonal nut

marked [A] and the (4) four screws marked [200].

The HAJK 1/4 circuit board can then be removed.

(Photo. 4, 5)

7. IN circuit board (time required: about 4 minutes)

7-1. Remove the top cover. (See Procedure 1.)

7-2.

Remove the front panel. (See Procedure 2.)

7-3.

Remove the HAJK 1/4 circuit board. (See Procedure 6.)

7-4.

Remove the IN circuit board pulling the hook of the

card holder. (Photo. 6, 7)

Locking card spacer

(ロッキングカードスペーサ)

Locking card spacer

(ロッキングカードスペーサ)

[140]

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MLA8

12

[100]: Bonding Tapping Screw-B 3.0x8 MFZN2BL (VN413300) +ボンディングBタイト

[120]: Hex. Locking Screw JFS-2.6S-BIW (VS604900) 6角ロックネジ

[125]: Pan Head Screw 2.6x6 MFZN2BL (VC990500) +ナベ小ネジ

[210]: Knob (VJ859500) スライドツマミ

[350]: Knob (WC583800) ノブD12

(Photo. 8) (Photo. 9)

8. HAJK3/4シート（所要時間:約3分）

8-1. トップカバーを外します。(1項参照)

8-2. [120]の六角ロックネジ2本とロッキングカー

ド

 スペーサ2本を外して、HAJK3/4シートを外



 します。(Photo. 4, 8)

9. HAJK2/4シート（所要時間:約4分）

9-1. トップカバーを外します。(1項参照)

9-2. HAJK3/4シートを外します。(8項参照)

9-3.

[100]のネジ16本と[125]のネジ8本を外し、[110]

のネジ6本を外して、HAJK2/4シートを外し



 ます。(Photo.4,9)

8.

HAJK 3/4 Circuit Board (time required: about 3 minutes)

8-1 Remove the top cover. (See Procedure 1.)

8-2

Remove the two (2) hexagonal locking screws marked

[120] and the two (2) locking card spacer. The HAJK

3/4 circuit board can then be removed. (Photo. 4, 8)

9.

HAJK 2/4 Circuit Board (time required: about 4 minutes)

9-1 Remove the top cover. (See Procedure 1.)

9-2

Remove the HKJK 3/4 circuit board. (See Procedure 8.)

9-3 Remove the sixteen (16) screws marked [100], the

eight (8) screws marked [125] and the six (6) screws

marked [110]. The HAJK 2/4 circuit board can then

be removed. (Photo. 4, 9)

HAJK 3/4

[120]

[125]

[100]

(Photo. 5) (Photo. 6)

[Photo. 7]

(Photo. 7)

IN

[A]

[210]

[350]

Card holder

(カードホルダ)

Card holder

(カードホルダ)

Hook

(フック)

Hook

(フック)

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MLA8

(Photo. 10) (Photo. 11)

[170], [250]: Bind Head Tapping Screw-S 3.0x6 MFZN2BL (EP630210) +バインドSタイト

10. HAJK4/4シート（所要時間:約3分）

10-1.

トップカバーを外します。(1項参照)

10-2.

フロントパネルを外します。(2項参照)

10-3.

[250]のネジ1本を外して、HAJK4/4シートを



 外します。(Photo.10)

11. PS2/2シート（所要時間:約3分）

11-1.

トップカバーを外します。(1項参照)

11-2.

フロントパネルを外します。(2項参照)

11-3.

ボタンPSWを外し、[170]のネジ2本とロッキ



 ングカードスペーサを外して、PS2/2シート



 を外します。(Photo.10,11)

10.

HAJK 4/4 Circuit Board (time required: about 3 minutes)

10-1.

Remove the top cover. (See Procedure 1.)

10-2.

Remove the front panel. (See Procedure 2.)

10-3.

Remove the screw marked [250]. The HAJK 4/4

circuit board can then be removed. (Photo. 10)

11.

PS 2/2 circuit board (time required: about 3 minutes)

11-1.

Remove the top cover. (See Procedure 1.)

11-2.

Remove the front panel. (See Procedure 2.)

11-3.

Remove the PSW button, the two (2) screws marked

[170] and the locking card spacer. The PS 2/2 circuit

board can then be removed. (Photo. 10, 11)

Button, PSW

(ボタンPSW)

Button, PSW

(ボタンPSW)

HAJK 4/4 PS 2/2

[170]

[250]

Locking card spacer

(ロッキングカードスペーサ)

Locking card spacer

(ロッキングカードスペーサ)

NJM4580M-D (TE2) (X5025A00)

Dual Operational Amplifier

HAJK: IC101, 102, 201, 202, 301, 302,

401,402, 501, 502, 601, 602, 701,

703, 801, 802

NJM2068MD-TE2 (X3505A00)

Dual Operational Amplifier

IN: IC101

1

2

3

4

8

7

6

5

Output A

Non-Inverting

Input A

-DC Voltage

Supply

(GND)

+DC Voltage

Supply

Output B

Inverting

Input B

Non-Inverting

Input B

Inverting

Input A

+-

A

B

1

2

3

4-V

8

7

6

5

Output A +V

Non-Inverting

Input A

-DC Voltage Supply

+DC Voltage

Supply

Output B

Inverting

Input B

Non-Inverting

Input B

Inverting

Input A

+-

■ IC BLOCK DIAGRAM（ICブロック図）

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MLA8

14

GAIN 1

ON

+48V

OFF

GAIN 2

ON

+48V

OFF

GAIN 3

ON

+48V

OFF

GAIN 4

ON

+48V

OFF ON

+48V

OFF

A

A’

●

HAJK 1/4 Circuit Board

（

HAJK1/4

シート）

to HAJK 2/4-CN108

to IN-CN102

to IN-CN103

to HAJK 2/4-CN308

to IN-CN102 to IN-CN102

to IN-CN103 to IN-CN103

to IN-CN102

to IN-CN103

■ CIRCUIT BOARDS（シート基板図）

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MLA8

GAIN 5

ON

+48V

OFF

GAIN 6

ON

+48V

OFF

GAIN 7

ON

+48V

OFF

GAIN 8

ON

+48V

POWER

OFF

A

A’

to HAJK 2/4-CN508 to HAJK 2/4-CN708

to IN-CN102

to IN-CN103

to IN-CN102

to IN-CN103

to IN-CN102

to IN-CN103

to IN-CN102

to IN-CN103

Components side (部品側)

2NA-WC13360

2

Components side

(部品側)

● HAJK 4/4 Circuit Board

（HAJK4/4シート）

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MLA8

16

● HAJK 1/4 Circuit Board（HAJK1/4シート）

● HAJK 4/4 Circuit Board（HAJK4/4シート）

B

B’

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(パターン側)

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17

MLA8

2NA-WC13360 2

B

B’

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MLA8

18

8

to PS-CN103

to HAJK 1/4-CN103

to HAJK 1/4-CN303

to HAJK 1/4-CN503

to HAJK 1/4-CN703

76 54 32 1 8

C

C’

●

HAJK 2/4 Circuit Board（HAJK2/4シート）

OUTPUT +4dBu

Components side (部品側)

●

HAJK 3/4 Circuit Board（HAJK3/4シート）

OUTPUT

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MLA8

Components side (部品側)

2NA-WC13340

1

2NA-WC13360

2

87654321

INPUT

Components side

(部品側)

(PEAK, SIGNAL 1): to HAJK 1/4-CN101

(PEAK, SIGNAL 2): to HAJK 1/4-CN201

(PEAK, SIGNAL 3): to HAJK 1/4-CN301

(PEAK, SIGNAL 4): to HAJK 1/4-CN401

(PEAK, SIGNAL 5): to HAJK 1/4-CN501

(PEAK, SIGNAL 6): to HAJK 1/4-CN601

(PEAK, SIGNAL 7): to HAJK 1/4-CN701

(PEAK, SIGNAL 8): to HAJK 1/4-CN801

(PEAK, SIGNAL 1): to HAJK 1/4-CN102

(PEAK, SIGNAL 2): to HAJK 1/4-CN202

(PEAK, SIGNAL 3): to HAJK 1/4-CN302

(PEAK, SIGNAL 4): to HAJK 1/4-CN402

(PEAK, SIGNAL 5): to HAJK 1/4-CN502

(PEAK, SIGNAL 6): to HAJK 1/4-CN602

(PEAK, SIGNAL 7): to HAJK 1/4-CN702

(PEAK, SIGNAL 8): to HAJK 1/4-CN802

(PEAK, SIGNAL 1): to HAJK 2/4-CN107

(PEAK, SIGNAL 2): to HAJK 2/4-CN207

(PEAK, SIGNAL 3): to HAJK 2/4-CN307

(PEAK, SIGNAL 4): to HAJK 2/4-CN407

(PEAK, SIGNAL 5): to HAJK 2/4-CN507

(PEAK, SIGNAL 6): to HAJK 2/4-CN607

(PEAK, SIGNAL 7): to HAJK 2/4-CN707

(PEAK, SIGNAL 8): to HAJK 2/4-CN807

●

IN Circuit Boards

x8（

IN

シート



x8）

80

26 dB

PEAK

SIGNAL

IN: CN103

IN: CN102

IN: CN101

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MLA8

20

●

HAJK 2/4 Circuit Board（HAJK2/4シート）

●

IN Circuit Board（INシート）

Pattern side

(パターン側)

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Yamaha MLA8 Building instructions

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