Pioneer GR-408 User manual

ORDER NO.
PIONEER ELECTRONIC CORPORATION 4-1, Meguro 1-Chome, Meguro-ku, Tokyo 153-8654, Japan
PIONEER ELECTRONICS SERVICE, INC. P.O. Box 1760, Long Beach, CA 90801-1760, U.S.A.
PIONEER ELECTRONIC (EUROPE) N.V. Haven 1087, Keetberglaan 1, 9120 Melsele, Belgium
PIONEER ELECTRONICS ASIACENTRE PTE. LTD. 253 Alexandra Road, #04-01, Singapore 159936
PIONEER ELECTRONIC CORPORATION 1998
c
GR-408
RRV2059
1. SAFETY INFORMATION ...................................... 2
2. EXPLODED VIEWS AND PARTS LIST................ 3
3. SCHEMATIC DIAGRAM ....................................... 6
4. PCB CONNECTION DIAGRAM............................ 8
5. PCB PARTS LIST ............................................... 10
6. ADJUSTMENT .................................................... 10
7. GENERAL INFORMATION ................................ 11
7.1 IC .................................................................. 11
8. PANEL FACILITIES AND SPECIFICATIONS .... 13
CONTENTS
T – IZK DEC. 1998 Printed in Japan
THIS MANUAL IS APPLICABLE TO THE FOLLOWING MODEL(S) AND TYPE(S).
GRAPHIC EQUALIZER
Type Model Power Requirement Remarks
GR-408
KUCXCN AC120V

2
GR-408
1. SAFETY INFORMATION
This service manual is intended for qualified service technicians ; it is not meant for the casual do-it-
yourselfer. Qualified technicians have the necessary test equipment and tools, and have been trained
to properly and safely repair complex products such as those covered by this manual.
Improperly performed repairs can adversely affect the safety and reliability of the product and may
void the warranty. If you are not qualified to perform the repair of this product properly and safely, you
should not risk trying to do so and refer the repair to a qualified service technician.
WARNING
This product contains lead in solder and certain electrical parts contain chemicals which are known to the state of California to cause
cancer, birth defects or other reproductive harm. Health & Safety Code Section 25249.6 – Proposition 65
NOTICE
(FOR CANADIAN MODEL ONLY)
Fuse symbols (fast operating fuse) and/or (slow operating fuse) on PCB indicate that replacement parts must
be of identical designation.
REMARQUE
(POUR MODÈLE CANADIEN SEULEMENT)
Les symboles de fusible (fusible de type rapide) et/ou (fusible de type lent) sur CCI indiquent que les pièces
de remplacement doivent avoir la même désignation.
ANY MEASUREMENTS NOT WITHIN THE LIMITS
OUTLINED ABOVE ARE INDICATIVE OF A POTENTIAL
SHOCK HAZARD AND MUST BE CORRECTED BEFORE
RETURNING THE APPLIANCE TO THE CUSTOMER.
2. PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in the appliance
have special safety related characteristics. These are
often not evident from visual inspection nor the protection
afforded by them necessarily can be obtained by using
replacement components rated for voltage, wattage, etc.
Replacement parts which have these special safety
characteristics are identified in this Service Manual.
Electrical components having such features are identified
by marking with a on the schematics and on the parts list
in this Service Manual.
The use of a substitute replacement component which does
not have the same safety characteristics as the PIONEER
recommended replacement one, shown in the parts list in
this Service Manual, may create shock, fire, or other hazards.
Product Safety is continuously under review and new
instructions are issued from time to time. For the latest
information, always consult the current PIONEER Service
Manual. A subscription to, or additional copies of, PIONEER
Service Manual may be obtained at a nominal charge from
PIONEER.
1. SAFETY PRECAUTIONS
The following check should be performed for the
continued protection of the customer and service
technician.
LEAKAGE CURRENT CHECK
Measure leakage current to a known earth ground (water
pipe, conduit, etc.) by connecting a leakage current tester
such as Simpson Model 229-2 or equivalent between the
earth ground and all exposed metal parts of the appliance
(input/output terminals, screwheads, metal overlays, control
shaft, etc.). Plug the AC line cord of the appliance directly
into a 120V AC 60Hz outlet and turn the AC power switch
on. Any current measured must not exceed 0.5mA.
(FOR USA MODEL ONLY)
Leakage
current
tester
Reading should
not be above
0.5mA
Device
under
test
Test all
exposed metal
surfaces
Also test with
plug reversed
(Using AC adapter
plug as required)
Earth
ground
AC Leakage Test

3
GR-408
2.1 PACKING •PACKING PARTS LIST
Mark No. Description Part No.
2. EXPLODED VIEWS AND PARTS LIST
NOTES: •Parts marked by "NSP" are generally unavailable because they are not in our Master Spare Parts List.
•The mark found on some component parts indicates the importance of the safety factor of the part.
Therefore, when replacing, be sure to use parts of identical designation.
•Screws adjacent to mark on the product are used for disassembly.
4
7
5
3
2
11
6
8
1 Pin Plug Cords (L = 1m) PDE1248
2 Polyform L 14904081-000
3 Polyform R 14904082-000
4 Polybag 20×26 15020026-510
5 Operating Instructions 15204080-0297
(English/French)
6 Carton Box 15304080-099
NSP 7 Warranty Card • • • • •
NSP 8 Packing Sheet • • • • •

4
GR-408
9
18
18
18
18
18
18
10
12
11
1
5
4
66
6
6
7
2
2
19
18
18
18
18
18
18
18
18
18
18
18
18
18
13
18
3
3
19
18
18
20
20 18
19
19
3
3
17
6
8
14
6
6
6
13
13
13
18
18
15
16
2.2 EXTERIOR SECTION

5
GR-408
•EXTERIOR SECTION PARTS LIST
Mark No. Description Part No.
1 Front Cabinet 10104080-001
2 EQ Bracket 12904082-010
3 EQ Knob(Black) 12704082-010
4 Power Button 12804080-010
5 EQ On/Off Button 12804080-110
6 Post 13004082-000
7 Rear Panel 18004085-101
NSP 8 Bottom Cabinet • • • • •
9 Bonnet Cover 18004083-010
10 Main Bord Assy (1/4) GR408-A
(EQ PCB)
11 Main Bord Assy (2/4) GR408-A
(POWER PCB)
12 Main Bord Assy (3/4) GR408-A
(EQ ON/OFF PCB)
13 Foot(Black)W/O H/S 13821007-010
14 Main Bord Assy (4/4) GR408-A
(JACK PCB)
15 AC Cord UL 02360040-006
NSP 16 Bushing • • • • •
17 Name Plate PAM1776
18 Screw BBZ30P080FZK
19 Screw IBZ30P080FMC
20 Screw BPZ26P080FMC

GR-408
6
A
B
C
D
1234
1234
3. SCHEMATIC DIAGRAM
A
3.1 MAIN BOARD ASSY
AC CORD UL
02360040-006
IC1B
LA6458
S
INPUT
INPUT
B
IN
BU
F
A
M
VR KNOB LED
GRAPHIC
EQUALIZER
ON/OFF
POWER SUPPLY
POWER OFF/ON
(LINE OUTPUT MUTE)
OFF ON
EQUALIZER
OFF / ON
-29
OUTPUT
V
C
-12
+12
0
0
0
0
+29
A
MAIN BOARD ASSY (GR408-A)
2/4
POWER PCB
A
4/4
JACK PCB
A
01804083-520
AC-2
AC-1
250V/630mA
SW2 : EQUALIZER OFF/ON
SW3 : POWER OFF/ON
C51
0.22µ/500V
R21
820/1W
R22
820/1W
R6
6.8k

GR-408
7
A
B
C
D
5678
5678
Note : When ordering service parts, be sure to refer to "EXPLODED VIEWS and PARTS LIST" or "PCB PARTS LIST".
A
IC1B
LA6458S
IC1A
LA6458S
INPUT BUFFER
AMP. OUTPUT
(EQUALIZER OFF)
GRAPHIC
EQUALIZER
GRAPHIC
EQUALIZER
INPUT
BUFFER
AMP.
INPUT
BUFFER
AMP.
GRAPHIC
EQUALIZER
INPUT
GRAPHIC
EQUALIZER
INPUT
GRAPHIC
EQUALIZER
INPUT
EQUALIZER
OFF / ON
EQUALIZER
OFF / ON
OUTPUT
GRAPHIC
EQUALIZER
OUTPUT
V
EE
V
CC
GND
V
EE
V
CC
V EE
V CC
V CC
GND
GRAPHIC
EQUALIZER
OUTPUT
GRAPHIC
EQUALIZER
OUTPUT
GRAPHIC
EQUALIZER
OUTPUT
GRAPHIC
EQUALIZER
OUTPUT
GRAPHIC
EQUALIZER
OUTPUT
VR1-VR14 : 01110203-230
GRAPHIC
EQUALIZER
OUTPUT
0
0
0
+12
0
0
0
+12
-12
+12
-12
0
0
0
0 0 0 0 0
0 0 0 0
0
0 0 0 0 0
+12
-12
0
0
0
0 0 0 0 0
0 0 0 0
0
0 0 0 0 0
1/4 EQ PCB
A
3/4 EQ ON/OFF PCB
A
R36
6.8k
6.8k
VR8
C19
R6
6.8k
R7
6.8k

GR-408
8
A
B
C
D
1234
1234
4. PCB CONNECTION DIAGRAM
A
4.1 MAIN BOARD ASSY
4/4 JACK PCB
A
1/4 EQ PCB
A
2/4 POWER PCB
NEUTRAL
WHITE
LIVE
A
SIDE A
NOTE FOR PCB DIAGRAMS :
1. Part numbers in PCB diagrams match those in the schematic
diagrams.
2. The parts mounted on this PCB include all necessary parts for
several destinations.
For further information for respective destinations, be sure to
check with the schematic diagram.
3. View point of PCB diagrams.
Capacitor
Connector
P.C.Board Chip Part
SIDE A
SIDE B

GR-408
9
A
B
C
D
5678
5678
A
B
3/4 EQ ON/OFF PCB
A
IC3 IC2 IC1
POWER CORD
AC
SIDE A
MAIN BOARD ASSY
A

10
GR-408
Mark No. Description Part No. Mark No. Description Part No.
LIST OF ASSEMBLIES
MAIN BOARD ASSY GR408-A
NSP EQ PCB • • • • •
NSP POWER PCB • • • • •
NSP EQ ON/OFF PCB • • • • •
NSP JACK PCB • • • • •
MAIN BOARD ASSY
SEMICONDUCTORS
IC2,IC3 AUDIO IC M5229P
IC1 IC LA6458SS 00206458-040
LED1 LED 01912000-110
SWITCHES SW SK-22F03G5 02012205-110
SW PBS-42H03-F18 02014218-110
RESISTOR
VR1-VR14 SLIDE VR. 01110203-230
OTHERS
T1 TRANSFORMER EI-35 01804083-520
Mark No. Description Part No.
5. PCB PARTS LIST
NOTES: •Parts marked by "NSP" are generally unavailable because they are not in our Master Spare Parts List.
•The mark found on some component parts indicates the importance of the safety factor of the part.
Therefore, when replacing, be sure to use parts of identical designation.
•When ordering resistors, first convert resistance values into code form as shown in the following examples.
Ex.1 When there are 2 effective digits (any digit apart from 0), such as 560 ohm and 47k ohm (tolerance is shown by J=5%,
and K=10%).
560 Ω→56 × 101→561 ........................................................ RD1/4PU 56
1
J
47k Ω→47 × 103→473 ........................................................ RD1/4PU
4 7
3J
0.5 Ω→R50 ..................................................................................... RN2H R5
0
K
1 Ω→1R0 ..................................................................................... RS1P
1
R0K
Ex.2 When there are 3 effective digits (such as in high precision metal film resistors).
5.62k Ω→ 562 × 101→5621 ...................................................... RN1/4PC 56
2
1F
A
6. ADJUSTMENT
There is no information to be shown in this chapter.

11
GR-408
1IN 1
NF 1
IN 2
NF 2
IN 3
NF 3
IN 4
NF 4
IN 5
NF 5
IN 1 NF 1 IN 2 NF 2 IN 3 NF 3 IN 4 NF 4 IN 5 NF 5
–Vcc
–Vcc
GND
GND
+Vcc
+Vcc
OUTPUT
OUTPUT
NON-INVERTING INPUT
INVERTING
INPUT
INVERTING INPUT
NON-
INVERTING
INPUT
NF 7
NF 7
IN 7
IN 7
NF 6
NF 6
IN 6
IN 6
10k 10k
47k
560
47k
560
47k
560
47k 47k
560
560
560
47k47k47k
560
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
20 19 18 17 16 15 14 13 12 11
1 2 3 4 5 6 7 8 9 10
7. GENERAL INFORMATION
• The information shown in the list is basic information and may not correspond exactly to that shown in the schematic diagrams.
M5229P (MAIN BOARD ASSY : IC2, IC3)
• Graphic Equalizer
•Pin Arrangement
7.1 IC
•Block Diagram
•Pin Function
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11NI
agnitcennocybretlifssapdnabehtesopmoC slanimretFNdnaslanimretNIhtiwroticapac ebnacniagehtdna,rehtohcaeottxendetacol edils(rotsiserelbairavagnitcennocybputes .)emulov
116NI agnitcennocybretlifssapdnabehtesopmoC slanimretFNdnaslanimretNIhtiwroticapac ebnacniagehtdna,rehtohcaeottxendetacol edils(rotsiserelbairavagnitcennocybputes .)emulov
21FN216FN
32NI317NI
42FN417FN
53NI51
gnitrevni-noN tupni
.pmaPOtuptuorofniptupnignitrevni-noN
63FN61
tupnignitrevnI
.pmaPOtuptuorofniptupnignitrevnI
74NI71TUPTUO.pmaPOtuptuorofniptuptuO
84FN81ccV+nipylppusrewopevitisoP
95NI91DNGnipdnuorG
015FN02ccV–nipylppusrewopevitageN

12
GR-408
LA6458S (MAIN BOARD ASSY : IC1)
• Input Buffer Amplifier
•Pin Arrangement
1
Vcc VOUT1
VOUT1
VOUT2
VOUT2
VIN-1
VIN-1
VIN+1
VIN+1
VIN+2
VIN+2
VIN-2
VIN-2
VEE
VEE
Vcc
Vcc
23456789
1,9
4
3
5
2 8
7
6
•Block Diagram

13
GR-408
8. PANEL FACILITIES AND SPECIFICATIONS
•FRONT PANEL FACILITIES
Equalizer ON indicator
1 2
3
1POWER switch (POWER OFF / ON)
When this switch is set to the ON position, power is supplied
to the unit’s main circuits (Equalizer indicators lights).
NOTE:
Even when performing playback without using the functions
of this component, be sure that its power switch is ON. If
the power switch is OFF, no sound will be produced from
the speakers.
2EQUALIZER button (EQUALIZER OFF / ON)
When this button is pressed, the equalizer ON indicator lights
and its functions become operative. When pressed once again,
this indicator go out and the unit’s functions are turned OFF,
Use this button in the following manner:
ON: When using the equalizer to add sound compen-
sation while performing mixing operations with
program sources (FM broadcasts, CD play, tape
playback, etc.).
OFF: When not using the equalizer, but playing back or
recording program sources without compensation.
3Equalizer controls
These are equalizer controls for the bands 60 Hz, 150 Hz,
400 Hz, 1 kHz, 2.4 kHz, 6 kHz and 15 kHz.
When the equalizer button has been set to ON, these controls
may be adjusted. When a control is raised upwards from the
“0” position, the frequency band corresponding to that control
willbe emphasized;whenthe controlsislowered, thefrequency
band will be attenuated. These controls can be used
independently for right and left channels.
NOTE:
In order to protect your speakers from damage resulting
from excessively large inputs, whenever augmenting high-
frequency sound over a wide range, be sure not to raise
your amplifier’s sound volume too high.
Left channel
Equalizer
indicators
Right channel
Equalizer
indicators

14
GR-408
+0
–3
•SPECIFICATIONS
Accessories
Pin-plug cords : PDE1248 (L=1m) ×2
Input terminals (Reference input level/Input impedance)
INPUT .......................................................... 150 mV/50 kΩ
Gain............................................................................. -2 dB
Output terminals
(Reference output level/Output impedance)
OUTPUT ..................................................... 150 mV/3.3 kΩ
Harmonic distortion (20 Hz ~ 20 kHz, Output 1V)
.................................................................................. 0.03 %
Frequency response
INPUT ................................................... 20Hz~20kHz dB
Equalizer bands
Center frequencies
................................................60 Hz, 150 Hz, 400 Hz,1 kHz
2.4 kHz, 6 kHz, 15 kHz
Variable range .......................................................... ±10 dB
SN ratio (IHF,A network, short circuit, 1V)
INPUT ......................................................................106 dB
Electrical section, miscellaneous
Power requirements ................................... AC 120 V, 60 Hz
Power consumption.........................................................6 W
External dimensions (W x H x D) .......... 420 x 85 x 214 mm
16-9/16 x 3-3/8 x 8-7/16 in.
Weight ................................................... 2.2 kg (4 lb. 14 oz.)
Accessories
Pin-plug cords .................................................................... 2
Operating Instructions ........................................................ 1
NOTE:
Specifications and the design are subject to possible modifi-
cations without notice, due to improvements.
Red
White
Red
White