Yamaha GF-12, GF-16, GF-24 Service manual

MIXING CONSOLE

SERVICE MANUAL

PA

011442

GF24 19990410-168000 GF16 19990410-128000 GF12 19990410-108000

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 per-

IMPORTANT : This presentation or sale of this manual to any individual or firm does not constitute authorization certifi-

The data provided is belived 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

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

sonal 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.

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

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

to the unit.

LITHIUM BA TTERY HANDLING

This product uses a lithium battery for memory back-up.

WARNING : Lithium batteries are dangerous because they can be exploded by improper handling. Observe the following pre-

Leave lithium battery replacement to qualified service personnel. Always replace with batteries of the same type. When installing on the PC board by soldering, solder using the connection terminals provided on the battery cells. Never solder directly to the cells. Perform the soldering as quickly as possible. Never reverse the battery polarities when installing. Do not short the batteries. Do not attempt to recharge these batteries. Do not disasemble the batteries. Never heat batteries or throw them into fire.

ADVARSEL!

Lithiumbatteri-Eksplosionsfare ved fejlagtig handtering. Udskiftning ma kun ske med batteri af samme fabrikat og type. lever det brugte batteri tilbage til leverandren.

VARNING

Explosionsfara vid felaktigt batteribyte. Anvand samma batterityp eller en ekvivalent typ som rekommenderas av apparattillverkaren. Kassera anvant batteri enligt fabrikantens instruktion.

VAROITUS

Paristo voi rajahtaa, jos se on virheellisesti asennettu. Vaihda paristo ainoastaan laitevalmistajan suosittelemaan tyyppiiin. Havita kaytetty paristo valmistajan ohjeiden mukaisesti. The following information complies with Dutch official Gazette 1995. 45; ESSENTIALS OF ORDER ON THE COLLECTION OF BATTERIES.

• Please refer to the diassembly procedure for the removal of Back-up Battery.

• Leest u voor het verwijderen van de backup batterij deze beschrijving.

cautions when handling or replacing lithium batteries.

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 IN YOUR MOUTH FOR ANY REASON WHAT SO EVER!

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

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

2

Input terminals

Gain trim

Actual load impedance

For use with

nominal

Input level

Connector

Sensitivity

†1

†1. Sensitivity is the lowest level that will produce an output of +4 dB (1.23 V) or the nominal output level when the unit is set at maximum

gain. (All faders and level controls are at maximum positions.)

Nominal Max. before clip

INPUT A, B (1–20, 1–12, 1–8)

MAX

3 kohm

50–600 ohm Mics

–86 dB (38.8 µV) –60 dB (0.775 mV) –40 dB (7.75 mV)

A: XLR-3-31 type

†2

B: Phone jack

†2

†2. Balanced.

MIN –42 dB (6.16 mV) –16 dB (123 mV) +4 dB (1.23 V)

ST INPUT A, B (21–24, 13–16, 9–12)

MAX

10 kohm 600 ohm Lines

–60 dB (0.775 mV) –34 dB (15.5 mV) –14 dB (155 mV)

A: Phone jack

†3

B: Phone jack

†3

†3. Unbalanced.

• When dB represents a speciﬁc voltage, 0 dB is referenced to 0.775 Vrms, 0 dBV is referenced to 1 Vrms.

MIN –16 dB (123 mV) +10 dB (2.45 V) +30 dB (24.5 V)

AUX RTN IN (1, 2) 10 kohm 600 ohm Lines –12 dB (195 mV) +4 dB (1.23 V) +20 dB (7.75 V)

Phone jack

†3

TAPE IN (L, R) 10 kohm 600 ohm Lines –26 dBV (50.1 mV) –10 dBV (316 mV) +8 dBV (2.51 V) Phone jack

†3

CH INSERT IN (1–20, 1–12, 1–8)

10 kohm 600 ohm Lines –26 dB (38.8 mV) 0 dB (775 mV) +20 dB (7.75 V)

Phone jack (I/O)

†3

ST INSERT IN (L, R) 10 kohm 600 ohm Lines –10 dB (245 mV) 0 dB (775 mV) +20 dB (7.75 V)

Output terminals

Actual source

impedance

For use with

nominal

Output level

Connector

Nominal Max. before clip

ST OUT (L, R) 600 ohm Lines +4 dB (1.23 V) +24 dB (12.3 V)

XLR-3-32 type

†1

†1. Balanced.

MONO OUT 600 ohm Lines +4 dB (1.23 V) +24 dB (12.3 V) GROUP OUT (1–4) 600 ohm Lines +4 dB (1.23 V) +20 dB (7.75 V) Phone jack

†2

†2. Unbalanced.

• When dB represents a speciﬁc voltage, 0 dB is referenced to 0.775 Vrms, 0 dBV is referenced 1 Vrms.

AUX OUT (1–6) 600 ohm Lines +4 dB (1.23 V) +24 dB (12.3 V) Phone jack

†1

C-R OUT (L, R) 600 ohm Lines +4 dB (1.23 V) +20 dB (7.75 V) Phone jack

†2

REC OUT (L, R) 10 kohm Lines –10 dBV (316 mV) +10 dBV (3.16 V) Phone jack

†2

CH INSERT OUT (1–20, 1–12, 1–8)

10 kohm Lines 0 dB (775 mV) +20 dB (7.75 V)

Phone jack (I/O)

†2

ST INSERT OUT (L, R) 10 kohm Lines 0 dB (775 mV) +20 dB (7.75 V) PHONES OUT 40 ohm Phones 3 mW 100 mW ST phone jack

†2

150 ohm 150 ohm

75 ohm

150 ohm

75 ohm

600 ohm

600 ohm 100 ohm

SPECIFICATIONS

General specifications Input specifications

GF24/12 GF16/12 GF12/12

Frequency response

Total harmonic distortion

20 Hz–20 kHz +1 dB, –2 dB @+4 dB into 600 ohm (GROUP OUT, AUX OUT, ST OUT, MONO OUT)

Less than 0.1 %, @20 Hz–20 kHz, +14 dB into 600 ohm (GROUP OUT, AUX OUT, ST OUT, MONO OUT)

Input gain control: minimum

–128 dB equivalent input noise –95 dB residual output noise (GROUP OUT, AUX OUT, ST OUT, MONO OUT)

Master fader: nominal level All channel faders: minimum All channel assign switches: off

Master fader: nominal level All channel faders, all AUX level controls: minimum

Master fader, one channel fader, assign switch on, AUX level control: nominal level One channel gain control: maximum

Hum & noise

(Average, Rs=150Ω with 20 Hz–20 kHz BPF)

–86 dB (GROUP OUT, ST OUT, MONO OUT)

–81 dB (AUX OUT)

–64 dB (68 dB S/N) (GROUP OUT, AUX OUT, ST OUT)

84 dB CH IN to ST OUT

Maximum voltage gain

Crosstalk

(at 1 kHz)

CH input gain control 44 dB variable CH input PAD 0 dB/26 dB CH input HPF 80 Hz 12 dB/oct

CH input equalization

ST input equalization

84 dB CH IN to GROUP OUT 58 dB ST IN to ST OUT 58 dB ST IN to GROUP OUT

70 dB adjacent input 70 dB input to output

+/- 15 dB maximum HIGH 10 kHz shelving* MID 250 Hz–5 kHz peaking LOW 100 Hz shelving* * Turn over/roll off frequency of shelving: 3 dB below maximum variable level.

+/- 15 dB maximum HIGH 10 kHz shelving* MID 2.5 kHz peaking LOW 100 Hz shelving* * Turn over/roll off frequency of shelving: 3 dB below maximum variable level.

Meters 13 points LED meters x4 (GROUP 1–4 /ST L R, PFL•AFL•TAPE IN L R)

Output specifications

CH peak indicators Red LED on each channel turns on when Post EQ signal reaches the level –3 dB below clipping. Phantom power +48 V is supplied to electrically balanced inputs.

Power requirement

Power consumption GF24/12: 70 W, GF16/12: 70 W, GF12/12: 70 W

Dimensions (WxHxD)

Weight GF24/12: 20 kg, GF16/12: 16 kg, GF12/12: 14 kg

• 0 dB is referenced to 0.775 Vrms.

USA and Canada: 120 V AC 60 Hz Other: 230 V AC 50 Hz

GF24/12: 938×157×487 mm GF16/12: 701×157×487 mm GF12/12: 587×157×487 mm

3

GF24/12 GF16/12 GF12/12

4

PANEL LAYOUT

Front panel

GF24/12 GF16/12 GF12/12

6379

26dB

GAIN

–34

+10

–15

–60

–15

–60

–15

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

PFL

Channel controls

GAIN

–34

+10

–60

–15

–60

–15

–60

–15

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

EVENLODD

1–2

3–4

PFL

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

PFL

GAIN

–34

+10

–60

–15

–60

–15

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

PFL

26dB

GAIN

–34

+10

–60

–15

–60

–15

–60

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

PFL

1. Mono input channels (page 6)

2. Stereo input channels (page 6)

GAIN

HIGH

MID

LOW

1

2

3

4

5

6 PAN

+10

–15

–15 +15

250 5K

–15 +15

010

234

10

5

0

5

10

15

20

30

40

AFL

MONO

010

POST

10

5 0

5

10 15

20 30 40

AFL

STEREO

PHANTOM +48V

OFF ON

METER SELECT

STEREO PFL•AFL

TAPE IN

010

C-R MONITOR

LEVEL

010

PHONES LEVEL

PHONES

POWER

PEAK +8 +5 +3 +1 0 –1 –3 –5 –7 –10 –15 –20

PHANTOM

GROUP

3

0

4

010

3

010

4

010

PEAK

+8 +5 +3 +1

0 –1 –3 –5 –7

–10

10

–15 –20

LR LR

STEREO PFL•AFL/TAPE IN

1

010

ON

MIXING CONSOLE

TAPE IN

10

5

0

5

10

15

20

30

40

AFL

PAN

RL

TO ST

RL

TO ST

10

5

0

5

10

15

20

30

40

AFL

21/22

23/24

20

1918171110987654321

26dB

GAIN

–34

+10

–60

–15

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10 15

20 30 40

PFL

26dB

GAIN

–34

+10

–60

–15

–60

–15

–60

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

PFL

1918171110987654321

A

B

26dB

GAIN

–34

+10

–15

–60

80

PEAK

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

–15 +15

AUX

PRE

1

010

2

010

PRE

3

010

4

010

PRE

5

010

6

010

PAN

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10 15

20 30 40

PFL

20

B

GAIN

–34

+10 –34

PEAK

HIGH

–15 +15

MID

–15 +15

LOW

–15 +15

1

010

2

010

3

010

4

010

5

010

6

010

BAL

GROUP

1

+10 –34

0

80

HIGH

MID

LOW

AUX

PRE

1

2

PRE

3

4

PRE

5

6 BAL

R

EVENLODD

ON

10

1–2

5

3–4

0

5

ST

10 15

20 30 40

PFL

10

80

PEAK

2

010

AUX

1

–15 +15

010

2

010

ST

–15 +15

010

23/2421/22

ON

ST

010

PFL PFL

AUX

1 AUX RETURN 2

PRE

10

5 0

PRE

5

10 15

20 30

PRE

40

AFL

AUX 1 AUX 2 AUX 3 AUX 4 AUX 5 AUX 6

PAN

R

RL

EVENLODD

TO ST

10

1–2

5

3–4

0

5

ST

10

15

20

30

40

AFL

PFL

GROUP 1 GROUP 2 GROUP 3 GROUP 4

21 54 8

Master controls

3. GROUP section (page 7)

4. AUX section (page 7)

5. STEREO/MONO section (page 7)

6. AUX RETURN section (page 7)

7. TAPE IN section (page 7)

8. Other controls/connectors (page 7)

9. Meter section (page 8)

Rear panel

Connectors (page 8)

+4dB

C-R OUT

POWER

ON/ OFF

MONO OUT

+4dBV

GROUP OUT

AUX OUT

STEREO OUT

ST INSERT I/O

+4dB

1234

+4dB (BALANCE)

(MONO)

INSERT I/O

OUT IN

B

INSERT I/O

21L

0dB

22R

INPUT

B

0dB

INPUT

B

INSERT I/O 0dB

INPUT

B

21L

22R

INPUT

A

INPUT

A

0dB

AUX RETURN

(MONO)

2LLRLR

+4dB

1L

INPUT

1R2R

23L

24R

123456

TAPE IN –10dBV

23L

RRLL

24R

REC OUT

+4dBV

–10dBV

INPUT

5

GF24/12 GF16/12 GF12/12

Channel controls

1. Mono input channels 1. Stereo input channels

26dB

GAIN

PEAK

–34

–60

80

+10

–16

4

HIGH

–15 +15

MID

250 5K

–15 +15

LOW

Pad switch

1

GAIN control

2

High pass filter switch

3

2

PEAK indicator

4

EQ controls (HIGH/MID/LOW)

5

3

AUX controls (1-6)

6

PRE switches

7

PAN control

8

ON switch

9

Group select switches

10

ST (stereo) switch

11

5

PFL (pre-fader listen) switch

12

Channel fader

13

GAIN

+10 –34

80

4

PEAK

HIGH

–15 +15

MID

–15 +15

LOW

A B

A/B switch

1

GAIN control

2

High pass filter switch

3

2

PEAK indicator

4

EQ controls (HIGH/MID/LOW)

5

3

AUX controls (1-6)

6

PRE switches

7

BAL (balance) control

8

ON switch

9

Group select switches

10

ST (stereo) switch

11

5

PFL (pre-fader listen) switch

12

Channel fader

13

–15 +15

AUX

1

2

3

6

4

PRE

010

PRE

010

6

7

5

6

PAN

PRE

010

R

L

EVEN

ODD

8

9

ON

10

1–2

5

3–4

0

5

ST

10 15

20 30 40

10

11

12

PFL

13

–15 +15

AUX

1

010

2

010

3

010

4

010

5

010

6

010

BAL

L

ODD

ON

10

5 0

5

10 15

20 30 40

PRE

R

EVEN

1–2

3–4

ST

PFL

7

8

9

10

11

12

13

6

Master controls

GF24/12 GF16/12 GF12/12

3. Group section

PAN

1

2

TO ST

3

4

GROUP 1 GROUP 2 GROUP 3 GROUP 4

PAN control

1

TO ST switch

2

Group fader

3

AFL (after-fader listen)

4

switch

5. STEREO/MONO section

PAN

RL

TO ST

10

5 0

5

10 15

20 30 40

AFL

PAN

RL

TO ST

10

5 0

5

10 15

20 30 40

AFL

PAN

RL

10

5 0

5

10 15

20 30 40

AFL

TO ST

RL

10

5 0

5

10 15

20 30 40

AFL

1 2

2

MONO

010

POST

10

5 0

5

10 15

20 30 40

4

AFL

STEREO

MONO (monaural) control

1

POST switch

2

STEREO fader

3

AFL (after-fader listen) switch

4

7. TAPE IN section

010

ON

TAPE IN

ST (stereo) control

1

ON switch

2

8. Other controlls/connectors

PHANTOM +48V

OFF ON

METER SELECT

STEREO PFL•AFL

GROUP

1

2

PHANTOM +48 V (phantom power supply)

1

switch METER SELECT switch

2

TAPE IN switch

3

C-R MONITOR LEVEL (control room monitor

4

2

level) control PHONES LEVEL (headphone) jack

5

PHONES (headphone) jack

6

4. AUX section

10

5 0

5

10 15

20 30

1

2

AUX fader

1

AFL (after-fader listen) switch

2

40

AFL

AUX 1 AUX 2 AUX 3 AUX 4 AUX 5 AUX 6

6. AUX RETURN section

TAPE IN

10

5 0

5

10 15

20 30 40

AFL

10

5 0

5

10 15

20 30 40

AFL

10

5 0

5

10 15

20 30 40

AFL

10

5 0

5

10 15

20 30 40

AFL

10

5 0

5

10 15

20 30 40

AFL

1

GROUP

1

0 0

2

010

AUX

1

010

2

010

ST

GROUP

GROUP 1/2, AUX 1/2 mix controls

1

3

10

AUX

ST

10

4

010

3

010

4

010

2

GROUP 3/4, AUX 3/4 mix controls

2

ST (stereo) controls

3

PFL (pre-fader listen) switch

4

010

C-R MONITOR

LEVEL

010

PHONES

LEVEL

3

4

5

3

010

4

PFL PFL

010

PHONES

6

1 AUX RETURN 2

7

GF24/12

W:

GF24/12: 938 GF16/12: 701 GF12/12: 587

300

119

D: 487

H: 157

119 119349

119 119463

119 119349351

GF12/12

GF16/12

GF24/12

Unit : mm

GF16/12 GF12/12

9. Meter section

PEAK

+8 +5 +3 +1

0 –1 –3 –5 –7

–10 –15 –20

LR LR

STEREO PFL•AFL/TAPE IN

1

Connectors

POWER

ON/ OFF

15

1

POWER

PEAK +8 +5 +3 +1 0 –1 –3 –5 –7 –10 –15 –20

0dB

PHANTOM

AUX RETURN

(MONO)

2LLRLR

TAPE IN –10dBV

234

+4dB

C-R OUT

ST INSERT I/O

GROUP OUT

AUX OUT

+4dB

1234

+4dB (BALANCE)

DIMENSIONS

2

Level meters

1

POWER indicator

2

PHANTOM (phantom power supply) indicator

3

11121314

+4dB

123456

1L

1R2R

23L

24R

10

INPUT

B

21L

22R

INSERT I/O

OUT IN

INSERT I/O 0dB

INPUT

B

INSERT I/O 0dB

INPUT

B

INSERT I/O 0dB

INPUT

B

9 8

AUX OUT jacks 1-6

1

MONO OUT jack

2

STEREO OUT jacks

3

TAPE IN connector

4

REC OUT jacks

5

INPUT A jacks 21-24

6

{13-16 on the GF16/12, 9-12 on the GF12/12} INPUT A jacks 1-20

7

{1-12 on the GF16/12, 1-8 on the GF12/12} INPUT B jacks 1-20

8

{1-12 on the GF16/12, 1-8 on the GF12/12} INSERT I/O jacks 1-20

9

{1-12 on the GF16/12, 1-8 on the GF12/12} INPUT B jacks 21-24

10

{13-16 on the GF16/12, 9-12 on the GF12/12} AUX RETURN jacks 1/2

11

ST INSERT I/O jacks

12

C-R OUT (control room monitor out) jacks

13

GROUP OUT jacks 1-4

14

POWER switch

15

8

23L

MONO OUT

+4dBV

STEREO OUT

+4dBV

RRLL

REC OUT –10dBV

24R

1 2 3 4 5 6

(MONO)

INPUT

A

21L

22R

INPUT

A

INPUT

7

INPUT

A

（単位）

BLOCK & LEVEL DIAGRAM

GF24/12 GF16/12 GF12/12

INPUT A

1-20 {1-12} {1-8}

INPUT B

INPUT A

INPUT B

No.

*1 *2 *3 *4

JK

*1,*3 (MONO)

*2,*4

*1,*3

*2,*4

GF12/12

9L

10R

11L

12R

PHANTOM

+48V

GF16/12

13L 14R 15L 16R

PAD

26dB

A

B

+48V

HA

GF24/12

21L 22R 23L 24R

IN MAS OUT MAS

JK

g

HIGH

PEAK

L

(MONO)

R

L

(MONO)

R

PEAK

PFL

ON

to PFL/AFL

ON

to PFL/AFL

PAN

BAL

GROUP 1

GROUP 2

GROUP 3

GROUP 4

PRE

AUX 1

AUX 2

ST

PFL

AUX 3

AUX 4

ST

to ST

ST

1-2

3-4

AUX 1

AUX 2

AUX 3

AUX 4

AUX 5

AUX 6

to ST

ST

1-2

3-4

AUX 1

AUX 2

AUX 3

AUX 4

AUX 5

AUX 6

to ST

to PFL/AFL

to ST

GAIN

HPF

80

INSERT I/O

3 Stage EQ

g

LOW

3 Stage EQ

LOW

3 Stage EQ

0dB

f

MID

AUX RETURN 1

AUX RETURN 2

g

MID

GROUP

AUX

654321

4321

ST

RL

PFL/AFL

L STEREO

OUT R

MONO OUT

(odd)

(even)

(odd)

(even)

LR

L R

TAPE IN

PAN

IC401

IC402

212 1

GROUP OUT 2-4:

Same as GROUP OUT 1

IC407

IC406

21

67

AUX OUT 2-6:

Same as AUX OUT 1

to Meter

AFL

TO ST

to PFL/AFL

GROUP OUT 1

AUX OUT 1

TAPE IN

from

L

R

1-20

Ch Input

{1-12} {1-8}

Ch Input *1,*3 Ch Input *2,*4

AUX RETURN 1, 2

21

IC301

ST

67

ST INSERT I/O L

ST INSERT I/O R

L

REC OUT

PAD

R

(L) (R)

L R

ON

21 IC421

67

MONOPOST

AFL

IC402

27

from

IC423

21

67

IC424

21

67

IC425

1

7

Ch Input

Ch Input *1,*3 Ch Input *2,*4

AUX RETURN 1, 2

GROUP OUT

AUX OUT

1-20 {1-12} {1-8}

from GROUP OUT 1

from GROUP OUT 2

from GROUP OUT 3

from GROUP OUT 4

C-R MONITOR

LEVEL

PHONES

LEVEL

METER SELECT

21

BA

IC426

67

BA

21

BA

IC427

67

BA

L

C-R OUT

R

PHONES

+20 dB

+10 dB

0 dB

–10 dB

–20 dB

–30 dB

–40 dB

–50 dB

–60 dB

PAD 26 dB

PAD 0 dB GAIN Min (–16 dB)

PAD 26 dB GAIN Max (–34 dB)

PAD 0 dB GAIN Max (–60 dB)

ST INPUT GAIN Min (+10 dB)GAIN Min (+10 dB)

INSERT I/O (0 dB)

ST INPUT GAIN Max (–30dB)

Ch Fader

AUX RETURN (+4 dB)

PFL

to PFL/AFL

AUX (–6 dB)

GROUP, AUX

GROUP OUT, AUX OUT (+4 dB)

TAPE IN (–10 dBV)

ST INSERT I/O (0 dB)

REC OUT (–10 dBV)

MONO

STEREO OUT, MONO OUT (+4 dB)

C-R OUT (+4 dB)

PHONES (3 mW, 40*)

+20 dB

+10 dB

0 dB

–10 dB

–20 dB

–30 dB

–40 dB

–50 dB

–60 dB

9

GF24/12 GF16/12 GF12/12

CIRCUIT BOARD LAYOUT

JK8 JK12 OUT

Transformer

(

24ch,12ch

)(

24ch,16ch

)

IN8 IN12 MAS 1/3

DC 2/2

MAS 2/3

DC 1/2

10

(

24ch,12ch

)(

24ch,16ch

)

MAS 3/3

KES-92558 2

WIRING

GF24/12 GF16/12 GF12/12

PANEL

,

Ass y

CN101

V320110

CN109

CN105

CN110

CN106

V320120

FFC Cable FFC Cable

V345610 V317890

CN102

CN101

CN105

CN106

CN102

V320110

CN109

CN110

V320120

CN103

V320110

CN111

CN107

CN112

CN108

V320120

V317840

CN101

1 2 3 4 5

MASIN8 IN12

CN102

MAS

3/3

CN108 CN107

V309820

1/3

CN115

CN114CN110CN113

V345610

CN116

V383340

CN105

CN109CN104

MAS

2/3

REAR PANEL

,

Ass y

BOTTOM

,

Ass y

CN102

CN103

V317830

CN102

CN103

CN104

CN101

CN102

OUT

JK12JK8

CN101CN101

CN105

: FFC Cable V317900

123

5

:

V317880

: V343740

4

CN103CN104

CN105

CN102

DC

2/2

CN101

Trans former

CN102

DC

to MAS 1/3 CN110

CN202CN203

to MAS 1/3 CN114

AC Cord

1/2

3NC2-V329380 2

11

GF24/12

[120b]

[120a]

[100c] [130]

[170a]

[90]

[110]

[290] [290]

[50]

[300]

[100a] [100a]

[100d] [100b]

[100d]

[90]

1/2

[170b]

[280]

[130]

[100c]

[110]

[90]

[120b]

DC

[120a]

GF16/12 GF12/12

DISASSEMBLY PROCEDURE

1. Panel Assembly

1-1 Remove the two (2) screws marked [170a] and the

two (2) screws marked [170b] from the corner pad. The corner pad can then be removed.(Fig. 1, 2, 3)

1-2 Remove the screws marked [100a] and [100b] on

the rear panel assembly. The quantity of the screws marked [100a] and [100b] are: [100a] : four (4) on the GF12-12 (Fig. 1)

: five (5) on the GF16-12 (Fig. 2) : six (6) on the GF24-12 (Fig. 3)

[100b] : one (1) on the GF12-12 (Fig. 1)

: one (1) on the GF16-12 (Fig. 2) : two (2) on the GF24-12 (Fig. 3)

1-3 Remove the screws marked [90] on the panel surface

of the panel assembly. The quantity of the screws marked [90] are: [90] : eight (8) on the GF12-12 (Fig. 1)

: eight (8) on the GF16-12 (Fig. 2) : ten (10) on the GF24-12 (Fig. 3)

1-4 Remove the six (6) screws marked [120a] on each

side of the panel assembly.

1-5 Remove the screws marked [290] on the bottom face

of the panel assembly on the fader side. The quantity of the screws marked [290] are: [290] : four (4) on the GF12-12 (Fig. 1)

: five (5) on the GF16-12 (Fig. 2) : six (6) on the GF24-12 (Fig. 3)

1-6 Remove the one (1) screw marked [120b] and the

screw marked [130] where the corner pad was removed. Loosening the screw marked [130] allows the panel assembly to open about 45 degrees. When working with the panel opened, secure the panel assembly by installing the fixed stay before beginning work.

1-7 While lifting the fader side of the panel assembly,

remove the panel assembly from the pawls located on the rear panel side of the bottom assembly.

2. Rear Panel Assembly

2-1 Remove the panel assembly. (See Procedure 1.) 2-2 Remove the two (2) screws marked [100c] on each

side of the section where the corner pad was removed.(Fig. 1, 2, 3)

2-3 Remove the screws marked [100d] on the rear panel.

The quantity of the screws marked [100d] are: [100d] : four (4) on the GF12-12 (Fig. 1)

: five (5) on the GF16-12 (Fig. 2) : six (6) on the GF24-12 (Fig. 3)

2-4 Remove the two (2) screws marked [280]. The meter

assembly can then be removed.

2-5 Remove the screws marked [110] on the panel surface.

The rear panel assembly can then be removed. The quantity of the screws marked [110] are: [110] : four (4) on the GF12-12 (Fig. 1)

: five (5) on the GF16-12 (Fig. 2) : six (6) on the GF24-12 (Fig. 3)

[GF 12/12]

[90]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [100]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [120]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [130]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [170]: Bind Head Tapping Screw-B 4.0X20 MFZN2BL (EP600190) [280]: Bind Head Tapping Screw-B 3.0X12 MFZN2BL (VQ074600) [290]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190)

Fig.1

＋バインドBタイト＋バインドBタイト＋バインドBタイト＋バインドBタイト

＋バインドBタイト＋バインドBタイト＋バインドBタイト

＋バインドBタイト

12

[90]

[110]

[100d]

[290]

[90]

[170a]

[290]

1/2

[50]

[90]

[100c]

[120b]

[130]

[100b]

[110]

[100d]

[100a]

[110]

[280]

[170]

[120b]

[130]

[300]

[100c]

[100a]

[90]

[100d]

[100b]

[110]

DC

[120a]

[GF 16/12] [GF 24/12]

GF24/12 GF16/12 GF12/12

[100c]

[120b]

[120a]

[130]

[170a]

[90]

[100a]

[110]

[290]

[100d]

[100a]

[100b]

[110]

DC

1/2

[50][90]

[100a]

[280]

[100d]

[110]

[290]

[170b]

[90]

[300]

[130]

[100c]

[120b]

[120a]

[90]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [100]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [120]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [130]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [170]: Bind Head Tapping Screw-B 4.0X20 MFZN2BL (EP600190) [280]: Bind Head Tapping Screw-B 3.0X12 MFZN2BL (VQ074600) [290]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190)

Fig.2 Fig.3

[90]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [100]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190) [120]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [130]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [170]: Bind Head Tapping Screw-B 4.0X20 MFZN2BL (EP600190) [280]: Bind Head Tapping Screw-B 3.0X12 MFZN2BL (VQ074600) [290]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190)

13

GF24/12

[65]

[50c]

[50a]

[50a][50a]

[50a]

[A]

1/3

3/3

IN8

MAS

[65]

[50a]

[50b]

[50a]

[50a] [50a]

1/3

[50a]

3/3

[50b]

[50b][50b]

IN12

MAS

[A]

GF16/12 GF12/12

3. MAS 1/3 Circuit Board

3-1 Remove the panel assembly. (See Procedure 1.) 3-2 Remove the rear panel assembly. (See Procedure 2.) 3-3 Remove the screws marked [65] on the ground bar.

The quantity of the screws marked [65] are: [65] : four (4) on the GF12-12 (Fig. 4)

: four (4) on the GF16-12 (Fig. 5) : six (6) on the GF24-12 (Fig. 6)

3-4 Remove the thirteen (13) fader knobs and the forty

(40) knobs on the panel surface.(Fig. 4, 5, 6)

3-5 Remove the sixteen (16) button screws that have a

hexagonal hole marked [50a] on the panel surface. The MAS 1/3 circuit board can then be removed. (Fig. 4, Fig. 5, Fig. 6)

4. IN12 Circuit Board (applicable to GF24/12 and GF16/12)

4-1 Remove the rear panel assembly. (See Procedure 1.) 4-2 Remove the rear panel assembly. (See Procedure 2.) 4-3 Remove the ground bar. (See Step 3-3.) 4-4 Remove the twelve (12) fader knobs and the one-

hundred and forty-four (144) knobs on the panel surface. (Fig. 5, Fig. 6)

4-5 Remove the twenty (20) button screws that have a

hexagonal hole marked [50b] on the panel surface. The IN 12 circuit board can then be removed. (Fig. 5, Fig. 6)

[50]: Screw 3X25 MFZN2BL (V3289800) [65]: Bind Head Screw 4.0X8 MFZN2BL (EG340360)

Fig.4

5.

IN8 Circuit Board (applicable to GF24/12 and GF12/12)

5-1 Remove the panel assembly. (See Procedure 1.) 5-2 Remove the rear panel assembly. (See Procedure 2.) 5-3 Remove the ground bar. (See Step 3-3.) 5-4 Remove the eight (8) fader knobs and the ninety-six

(96) knobs on the panel surface.

5-5 Remove the twelve (12) button screws that have a

hexagonal hole marked [50c] on the panel surface. The IN8 circuit board can then be removed. (Fig. 4, Fig. 6)

[50]: Screw 3X25 MFZN2BL (V3289800) [65]: Bind Head Screw 4.0X8 MFZN2BL (EG340360)

Fig.5

14

[20]

[50]

1/2

[50] [40]

[40]

[70]

[40]

DC

GF24/12 GF16/12 GF12/12

[65]

[50a]

[50b]

[50c]

[50a]

[A]

MAS

[50a]

MAS

[50b]

IN12

[50b]

IN8

[50c]

3/3

1/3

2/3MAS

Fig.7

8. DC 1/2 Circuit Board

8-1 Remove the panel assembly. (See Procedure 1.) 8-2 Remove the four (4) screws marked [50] and the

three (3) screws marked [300] securing the GND wire of the PSW. The power assembly can then be removed. (Fig. 1, Fig. 2, Fig. 3)

8-3 Remove the three (3) screws marked [70], the screw

marked [50], and the four (4) screws marked [40]. The DC 1/2 circuit board can then be removed. (Fig. 8)

[65]

[50]: Screw 3X25 MFZN2BL (V3289800) [65]: Bind Head Screw 4.0X8 MFZN2BL (EG340360)

6. MAS 2/3 Circuit Board

6-1 Remove the meter assembly . (See Step 2-4.) 6-2 Remove the four (4) screws marked [20]. The

MAS 2/3 circuit board can then be removed. (Fig. 7)

7. MAS 3/3 Circuit Board

7-1 Remove the panel assembly. (See Procedure 1.) 7-2 Remove the hexagonal nut marked [A] at the

right end of the panel surface. The MAS 3/3 circuit board can then be removed. (Fig. 4, Fig. 5, Fig. 6)

Fig.6

[40]: Power Supply Assembly GF24 J U (EG340190) [50]: Bind Head Tapping Screw-B 4.0X8 MFZN2BL (EG340190) [70]: Rear Panel Assembly GF24 (VZ765100)

Fig.8

15

GF24/12

2/2

[100e]

[40a]

Hexagonal nut

[40b]

Hexagonal

nut

[40d] [40d] [40d] [40d] [40d]

[110]

DC

OUT

JK

2/2

[100e]

Hexagonal nut

[40a] [40b]

Hexagonal nut

[40c] [40c] [40c] [40c] [40c] [40c] [40c] [40c]

[110]

DC

OUT

JK

GF16/12 GF12/12

9. DC 2/2 Circuit Board

9-1 Remove the panel assembly. (See Procedure 1.) 9-2 Remove the rear panel assembly. (See Procedure 2.) 9-3 Remove the two (2) screws marked [1 10] on the rear

panel. The DC 2/2 circuit board can then be pulled out. (Fig. 9, Fig. 10, Fig. 11)

10. OUT Circuit Board

10-1 Remove the panel assembly. (See Procedure 1.) 10-2 Remove the rear panel assembly .(See Procedure 2.) 10-3 Remove the six (6) screws marked [40a] on the rear

panel side of the DIN connectors, the two (2) screws marked [40b], and the twenty-two (22) hexagonal nuts fixing the jack. The OUT circuit board can then be removed. (Fig. 9, Fig. 10, Fig. 11)

11. JK12 Circuit Board (applicable to GF24/12 and GF16/12)

11-1 Remove the panel assembly. (See Procedure 1.) 11-2 Remove the rear panel assembly . (See Procedure 2.) 1 1-3 Remove the twenty-four (24) screws marked [40c],

of the DIN connectors on the rear panel side, and the twenty-four (24) hexagonal nuts fixing the jack. The JK12 circuit board can then be removed. (Fig. 10, Fig. 11)

[40]: Bonding Tapping Screw-B 3.0X8 MFZN2BL (VN413300) [100]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190)

12. JK8 Circuit Board (applicable to GF24/12 and GF12/12)

12-1 Remove the panel assembly. (See Procedure 1.) 12-2 Remove the rear panel assembly . (See Procedure 2.) 12-3 Remove the sixteen (16) screws marked [40d], of

the DIN connectors on the rear panel side, and the sixteen (16) hexagonal nuts fixing the jack. The JK8 circuit board can then be removed. (Fig. 9, Fig. 11)

13. Power Transformer

13-1 Remove the panel assembly. (See Procedure 1.) 13-2 Remove the rear panel assembly . (See Procedure 2.) 13-3 Remove the four (4) screws marked [100e] on the

rear panel surface. The power transformer can then be removed. (Fig. 9, Fig. 10, Fig. 11)

Fig.9

[40]: Bonding Tapping Screw-B 3.0X8 MFZN2BL (VN413300) [100]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190)

16

Fig.10

NJM2068L-D (XM356A00) Dual Operational Amplifier

NJM4580L (XF195A00

)

Dual Operational Amplifier

1A2 3 4 5 6 7 8

+IN

OUT

AAA

+V

+IN

OUT

BBB

+

B

+

1A2 3 4 5 6 7 8 9

+V IN V

+INOUT

AAA

+V IN

+IN OUT

BBB

+

B

+

IN INV

IC BLOCK DIAGRAM

GF24/12 GF16/12 GF12/12

[110]

DC

2/2

DC

Hexagonal nut

OUT

JK12 JK8

Hexagonal nut

JK12

JK8

[100e]

[40]: Bonding Tapping Screw-B 3.0X8 MFZN2BL (VN413300) [100]: Bind Head Tapping Screw-B 4.0X12 MFZN2BL (VR138400) [110]: Bind Head Tapping Screw-B 3.0X8 MFZN2BL (EP600190)

[40a] [40a] [40b]

[40c] [40d][40c] [40c] [40c] [40c] [40d] [40d] [40d]

Fig.11

17

GF24/12 GF16/12 GF12/12

CIRCUIT BOARDS

MAS 2/3 Circuit Board

MAS 1/3 Circuit Board

MAS 2/3 Circuit Board

Component side

CN116: to MAS 1/3

-CN115 CN115:

to MAS 2/3

-CN116

CN110: to DC

-CN202

CN113: to JK8-CN101 (GF12/12) to JK12-CN105 (GF24,16/12)

CN107: to MAS 3/3-CN108

CN108: to MAS 1/3-CN107

Component side

CN105: to OUT-CN105

CN109: to OUT-CN103

CN102: to OUT-CN102

CN104: to OUT-CN104

CN101: to OUT-CN101

Note: See parts list for details of circuit

board component parts.

Component side

18

CN112: to IN8-CN106(GF12/12) CN112: to IN12-CN108(GF24,16/12)

CN111: to IN8-CN105(GF12/12) CN111: to IN12-CN107(GF24,16/12)

MAS: 3NA-V288420

3

GF24/12 GF16/12 GF12/12

MAS 2/3 Circuit Board

Pattern side

MAS 1/3 Circuit Board

Pattern side

19

GF24/12 GF16/12 GF12/12

CN102: to JK8-CN102

IN8 Circuit Board

CN105: to MAS-CN111(GF12/12) CN105: to IN8-CN109(GF24/12)

20

CN101: to JK8-CN103

Component side

IN8: 3NA-V288400 1

GF24/12 GF16/12 GF12/12

Pattern side

21

GF24/12 GF16/12 GF12/12

CN103: to JK12-CN104

IN12 Circuit Board

CN108: to MAS 1/3-CN112

CN107: to MAS 1/3-CN111

CN102: to JK12-CN103

CN101: to JK12-CN102

22

CN110: to IN8-CN106

(GF24/12only)

CN109

CN109: to IN8-CN105

(GF24/12only)

Component side

IN12: 3NA-V288410 1

GF24/12 GF16/12 GF12/12

Pattern side

23

GF24/12 GF16/12 GF12/12

DC 1/2 Circuit Board

OUT Circuit Board

CN104: to MAS 1/3-CN104

CN103: to MAS 1/3-CN109

CN105: to MAS 1/3-CN105

CN101: to AC Code

Rear Panel GND

DC 2/2 Circuit Board

CN102: to Transformer

CN201: to Transformer CN202:

Component side

to MAS 1/3-CN110

CN203: to MAS 1/3-CN114

Component side

CN101: to MAS 1/3-CN101

CN102: to MAS 1/3-CN102

Component side

24

DC: 3NA-V288460 1

OUT: 3NA-V288450 1

JK8 Circuit Board

GF24/12 GF16/12 GF12/12

CN101: to MAS 1/3-CN113

JK12 Circuit Board

CN103: to IN8-CN102

CN102: to IN8-CN101

Component side

CN105: to MAS 1/3-CN113 CN101: to IN12-CN110

JK8: 3NA-V288430 JK12: 3NA-V288440 1

1

CN104: to IN12-CN103

to IN12-CN102 to IN12-CN101

(GF24/12 only)

Component side

25

GF24/12

ST Fader: AFL switch: MONO LEVEL control: POST switch: C-R MONITOR TAPE IN switch: LEVEL control: PHONES LEVEL control: AUX RETURN 1 GROUP 1, 2 level control: AUX 1, 2 level control: ST level control: PFL switch: AUX RETURN 2 GROUP 3, 4 level control: AUX 3, 4 level control: ST levels control: PFL switch: TAPE IN ST level control: ON switch: METER SELECT GROUP 1-4/ST L R, PFLE AFL/TAPE IN L R select switch:

PHANTOM PHANTOM switch:

Maximum ON during measurement only, OFF at all other times.

OFF Maximum

Maximum during measuring only, minimum at all other times.

Maximum during measuring only, minimum at all other times. Maximum during measuring only, minimum at all other times. Maximum during measuring only, minimum at all other times. ON during measurement only, OFF at all other times.

Maximum ON during measurement only, OFF at all other times.

ON during measurement only, OFF at all other times.

OFF

GF16/12 GF12/12

INSPECTIONS

1. PREPARATION

1-1 Unless specified, the signal applied should be a 1 kHz s ine wave and the impedan ce of the signal source shou ld be 150 ohms.

CH INSERT OUT, ST INSERT OUT, REC OUT: 10 Kohm GROUP OUT, AUX OUT, ST OUT, MONO OUT, C-R OUT: 600 ohm PHONES:

1-2 Unless specified, set the knobs as follows:

CH INPUT (1-8; 12; 20) PAD switch: GAIN trim: HPF switch: EQ (HIGH, MID, LOW) gain control: EQ (MID) FREQ control:

26

AUX 1 to 6 LEVEL control: AUX 3/4,5/6 PRE switch: PAN control: ON switch: Fader: PFL switch:

Stereo input (9-16; 21-24)

A/B switch: GAIN trim: HPF switch: EQ (HIGH, MID, LOW) gain control: AUX 1 to 6 LEVEL control: AUX 3/4, 5/6 PRE switch: BAL control: ON switch: Fader: PFL switch: MASTER

GROUP (1-4)

PAN control: TO ST switch: Fader: AFL switch: AUX (1-6) Fader: AFL switch:

40 ohm

OFF Maximum OFF Center Minimum Maximum ON during measurement only, OFF at all other times. Center ON during measurement only, OFF at all other times. Maximum OFF

OFF (A) Maximum OFF Center Maximum ON during measurement only, OFF at all other times. Center ON during measurement only, OFF at all other times. Maximum OFF

Center ON during measurement only, OFF at all other times. Maximum ON during measurement only, OFF at all other times.

Maximum ON during measurement only, OFF at all other times.

2-1 Gain

In status 1-1, the output levels should be within the range g iven in Tables 1 and 11. (For the items marked with an asterisk (*) in th e table below , refer to 2-2 Freq uency Response.) (For the items marked with two asterisk s (**) in the table below, r efer to 2-8 Dis tortio n.)

Table 1 : Input Terminal [INPUT CH T O 6, 1 2, 20] (Do not put any input into B.) [Unit: dBs]

Input Level

GAIN PAD AUX

PRE

PAN GROUP

(1 to 4)

OUT

AUX (1, 2) OUT

AUX

(3 to 6)

OUT

ST

(L, R)

OUT

GF24/12 GF16/12 GF12/12

C-R

(L, R) OUT

*1

-70 MAX OFF

-26 MIN OFF OFF L *

0 MIN ON OFF L +14 +/- 2 *2 - - - -

*1: When a signal is applied to the C-R MONIT OR OUT, you should turn the PFL switch "ON". *2: Measure only GROUP1.

1) The difference in the levels of the CH INPUTs (1 8; 12; 20) of each output should be less than 2 dB.

2) The difference in the levels of the GROUP (1 - 4 ) OUT; AUX (1, 2) OUT; AUX (3 - 6) OU T and ST ( L, R) OUT should be less than 2 dB.

Table 2 : INPUT B (CH INPUT 1 8; 12 ; 20 ) (Do not put any input into A.) [Unit: dBs]

Input Input

CH INPUT -70 MAX OFF -10 +/- 2 +14 +/- 2

OFF

ON L - - +10 +/- 2 - -

Level

L *, **

+14 +/- 2

(GROUP 1, 3)

R *, **

+14 +/- 2

(GROUP 2, 4)

+14 +/- 2 *2

GAIN PAD CH INSERT OUT GROUP 1 OUT

*, **

+10 +/- 2

- - *, **

----

*, **

+20 +/- 2

*, **

+14 +/- 2

(ST L)

+14 +/- 2

(ST R)

*, **

0 +/- 2

-

CH INSERT IN -10 MAX OFF - +14 +/- 2

1)

The difference in the levels of the CH INPUT (1 8; 12; 20 ) of each outpu t should be less than 2 dB.

2) The PAN VR should be turned fully counterclo ckwise.

27

GF24/12 GF16/12 GF12/12

Table 3 : ST INPUT A L (CH9; 11-13; 15-21; 23) (Do not put any input into CH 10; 12-14; 16-22; 24.)

Input Level

-44 MAX

GAIN AUX

PRE

OFF

ON L - - +13 +/- 2 - -

PAN GROUP

(1 to 4)

OUT

L *(GROUP 1 only)

**

+14 +/- 2

(GROUP 1, 3)

R *(GROUP 2 only)

**

+14 +/- 2

(GROUP 2, 4)

AUX

(1, 2)

OUT

**

+13 +/- 2

--**

AUX

(3 to 6)

OUT

**

+23 +/- 2**+14 +/- 2

ST

(L, R)

OUT

(ST L)

+14 +/- 2

(ST R)

[Unit: dBs]

C-R

(L, R) OUT

*1 **

0 +/- 2

-

0 MIN OFF

*1: Turn on the PFL switch when you measure th e C-R OU T.

1) The difference in the levels of the ST INPUT (9; 1 1-13; 15-21; 23 ) of each ou tput should be less than 2 dB.

2)

The difference in the levels of the GROUP (1-4) OUT; AUX (1, 2) OUT; AUX (3-6) OUT and ST (L, R) OUT should be less than 2 dB.

Table 4 : Input Terminal ST INPUT A R (CH10; 1 2-14; 16-22; 24 )

(Do not put any input into CH9; 11-13; 15-21; 23.) [Unit: dBs]

Input Level C-R (L) OUT

-44

1) The difference in the levels of the ST INPUT (10; 12-14; 16-22; 24) of each output should be less than 2 dB.

Table 5 : Input Terminal ST INPUT B (CH 9-16; 21-24)

Input Terminal

9; 11-13; 15-21; 23

GAIN C-R (R) OUT

L*

+14 +/ -2

(GROUP 1)

R +14 +/- 2

(GROUP 2)

PFL SW

ONMAX

Input

Level

-44 MAX ON

No output

GAIN PFL SW C-R

----

0+/-2

[Unit: dBs]

C-R

L OUT

0 +/- 2

R OUT

-

28

10; 12-14; 16-22; 24

1) Turn the ST INPUT A/B switch on at "ON (B)."

2) The difference in the levels of the ST INPUT (9 16; 22 - 24) of each output should be less than 2 dB.

-

0 +/- 2

Table 6: Input Terminal CH1 INPUT [Unit: dBs]

Input Level

GAIN POST

MONO OUT REC OUT (L,R)

GF24/12 GF16/12 GF12/12

OFF * , ** +10 +/- 2-70 MAX

ON

1) Turn on the ST assign switch of CH1 INPUT.

2) When the signal is applied to the MONO OUT , set the CH PAN to the center. When the signal is applied to the REC OUT, turn the CH PAN to L (for maximum turn counterclockwise) or R (for

3) maximum turn clockwise).

Table 7: Input Terminal CH1 INPUT [Unit: dBs]

Input

GAIN CH1 PAN

Level

-80 MAX

1) Turn on the GROUP (1-2; 3-4) assign switch of CH1.

2) Turn off the ST assign switch.

3) Turn on one of the TO ST switches in GROUP (1 - 4).

VR

R GROUP 2, 4

Select Switch

GROUP TO ST switch

+20 +/- 2 -

GROUP TO ST PAN ST L OUT ST R OUT

** -7.8 +/- 2

L +14 +/- 2 -L GROUP 1, 3 R - +14 +/- 2

L +14 +/- 2 R - +14 +/- 2

Table 8: Input terminal CH1 INPUT, OUTPUT C - R MONIT OR L R OUT

Input

Level

PAD AUX GROUP

GAIN

OFF OFF

PAN AUX

PRE

(1, 3)

AFL ON

L +10 +/- 2-80 MAX

R

- +10 +/- 2 - - * +10 +/- 2

GROUP

(2, 4)

AFL ON

- +6 +/- 2

(1, 2)

AFL ON

AUX

(3 to 6)

AFL ON

+16 +/- 2

[Unit: dBs]

ST (L, R)

AFL ON

* +10 +/- 2

(C-R L)

(C-R R)

29

GF24/12 GF16/12 GF12/12

Table 9 : Input terminal AUX RETURN

Input Input

Level

1L

(No plug for

1R)

2L

(No plug for

2R)

1R

2R

*1: Turn on the PFL switch when measuring the C-R OUT.

1) The difference in the level between the following should be less than 2 dB: GROUP (1 to 4) OUT; AUX (1 to 4) OUT; and ST (L,R) OUT.

Table 1 0: Input term inal TAPE IN L R

Input

TAPE IN L +20 +/- 2

TAPE IN R

*1 Set the TAPE IN ON switch to ON and the TAPE IN VR at max imum. *2 Set the C-R MONITOR LEVEL VR at maximum and the PFL.AFL/TAPE IN switch to ON. *3 Set the PHONES VR at maximum and the PFL.AFL/TAPE IN switch to ON.

-6

Input

Level

-7.8

GROUP

(1, 2)

OUT

*A**

+10 +/- 2

- *, **

GROUP 1

No output

GROUP 2

+10 +/- 2

-

ST L

OUT

*1

- +20 +/- 2

GROUP

(3, 4)

OUT

-**

+10 +/- 2

- AUX 1

GROUP 3

No output

GROUP 4

+10 +/- 2

ST R OUT

- +10 +/- 2

*1

AUX (1, 2) OUT

+10+/-2

-**

No output

AUX 2

+10 +/- 2

- AUX 3

C-R

L OUT

*2

- +10 +/- 2

AUX

(3, 4)

OUT

-**

+10 +/- 2**+10 +/- 2

- ST L

No output

AUX 4

+10 +/- 2

C-R

R OUT

- *, **

*2

ST(L, R)

OUT

+10 +/- 2

No output

+10 +/- 2

No output

+10 +/- 2

PHONES

L

-1 +/- 2 *3

-

ST R

ST L ST R

[Unit: dBs]

C-R

(L, R) OUT

*1

**

0 +/- 2

**

0 +/- 2

C-R L

No output

C-R R

0 +/- 2

C-R L

No output

C-R R 0 +/- 2

[Unit: dBs]

PHONES

R

-

*, **

-1 +/- 2 *3

Table 11: Input Terminal ST INSERT IN [Unit: dBs]

Input

ST INSERT L +4 +/- 2

ST INSERT R

1) The level difference between ST (L, R) OUT should be 2 dB or less.

2-2 Frequency Response

With the input signal frequency is set to 20 Hz and 20 kHz in the state as described in 2-15, check the level at each output terminal marked with an asterisk (*) in Table 1, Table 3, Table 6, Table 8, Table 9, and Table 10. It should fall within the range of +1 dB and -2 dB, using 1 kHz as a reference.

Input Level

-10

ST L OUT ST R OUT

-

- +4 +/- 2

30

Yamaha GF-12, GF-16, GF-24 Service manual

CONTENTS

SPECIFICATIONS

PANEL LAYOUT

DIMENSIONS

BLOCK & LEVEL DIAGRAM

CIRCUIT BOARD LAYOUT

WIRING

DISASSEMBLY PROCEDURE

IC BLOCK DIAGRAM

CIRCUIT BOARDS

INSPECTIONS