Yamaha A-s300 Service Manual

							A-S500/A-S300
10118 8
SERVICE MANUAL
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 specifi cally 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 specifi ed.  For these reasons, we advise 
all YAMAHA product owners that any 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 fi rm does not constitute authorization, certifi cation  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 
specifi cations are subject to change without notice or obligation to retrofi t.  Should any discrepancy appear to exist, please contact the 
distributors Service Division.
WARNING:  Static discharges can destroy expensive components.  Discharge any static electricity your body may have 
accumulated by grounding yourself to the ground buss in the unit (heavy gauge black wires connect to this buss).
IMPORTANT: Turn the unit OFF during disassembly and part replacement.  Recheck all work before you apply power to the unit.
■ CONTENTS
TO SERVICE PERSONNEL  ............................................ 2
IMPEDANCE SELECTOR  ............................................... 3
FRONT PANELS  ............................................................. 3
REAR PANELS  ........................................................... 4–8
REMOTE CONTROL PANEL  .......................................... 9
SPECIFICATIONS / 
€ß“7  ................................... 9–10
INTERNAL VIEW    .......................................................... 11
SERVICE PRECAUTIONS / 
±”ϵÌw«™Äò  ..... 11
DISASSEMBLY PROCEDURES / 

ür		q  ........... 12–15
UPDATING FIRMWARE /
  ..................................... 16–20SELF-DIAGNOSTIC FUNCTION / 
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…;ó£  ....................................... 21–27
AMP ADJUSTMENT /
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T  ....................... 28–29
IC DATA  ................................................................... 30–32
PIN CONNECTION DIAGRAMS  ............................. 33–34
BLOCK DIAGRAM  ........................................................ 35
PRINTED CIRCUIT BOARDS  ................................. 36–52
SCHEMATIC DIAGRAMS  ....................................... 53–61
REPLACEMENT PARTS LIST  ................................ 63–79
REMOTE CONTROL  ..................................................... 80
INTEGRATED AMPLIFIER
10.09
P.O.Box 1, Hamamatsu, Japan
Copyright © 2010   All rights reserved.
This manual is copyrighted by YAMAHA and may not be copied or
redistributed either in print or electronically without permission.
A-S500/A-S300 
						

							2
A-S500/A-S300
A-S500/A-S300
1.  Critical Components Information
Components having special characteristics are marked 
/  and 
must be replaced with parts having specifications equal to those 
originally installed.
2.  Leakage Current Measurement (For 120V Models Only)
When service has been completed, it is imperative to verify 
that all exposed conductive surfaces are properly insulated 
from supply circuits.
•  Meter impedance should be equivalent to 1500 ohms shunted 
by 0.15 μF.
■  TO SERVICE PERSONNEL
•  Leakage current must not exceed 0.5mA.
•  Be sure to test for leakage with the AC plug in both polari-
ties.
WALL
OUTLETEQUIPMENT
UNDER TESTAC LEAKAGE
TESTER OR
EQUIVALENT
INSULATING
TABLE
For U model
“CAUTION”
“F1: FOR CONTINUED PROTECTION AGAINST RISK OF FIRE, REPLACE ONLY WITH SAME TYPE 8A

(A-S500) 
/ 6A

(A-S300), 125V FUSE.”
For C model
CAUTION
F1:  REPLACE WITH SAME TYPE 8A (A-S500) / 6A (A-S300), 125V FUSE.
ATTENTION
F1:  UTILISER UN FUSIBLE DE RECHANGE DE MÉME TYPE DE 8A (A-S500) / 6A (A-S300), 125V.
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							3
A-S500/A-S300
A-S500/A-S300
■ IMPEDANCE SELECTOR
A-S500 (U, C, R, T, A, B, G, L models)
A-S300 (R, T, A, B, G, L, J models)
■ FRONT PANELS
WARNING:
Do not change the setting of the IMPEDANCE SELECTOR switch 
when the unit power is switched on, as doing so may damage 
the unit.
IMPEDANCE SELECTOR
A-S500
A-S300 
						

							4
A-S500/A-S300
A-S500/A-S300
A-S500 (U, C models)
■ REAR PANELS
A-S500 (R model)
A-S500 (T model)
A-S500 
						

							5
A-S500/A-S300
A-S500/A-S300
A-S500 (A model)
A-S500 (B model)
A-S500 (G model)
A-S500 
						

							6
A-S500/A-S300
A-S500/A-S300
A-S500 (L model)
A-S300 (R model)
A-S300 (T model)
A-S500
A-S300 
						

							7
A-S500/A-S300
A-S500/A-S300
A-S300 (A model)
A-S300 (B model)
A-S300 (G model)
A-S300 
						

							8
A-S500/A-S300
A-S500/A-S300
A-S300 (J model) A-S300 (L model)
A-S300 
						

							9
A-S500/A-S300
A-S500/A-S300
■  REMOTE CONTROL PANEL
RAS5
■ SPECIFICATIONS / 
€ß“7
■ Audio Section / 
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Minimum RMS Output Power (Power Amp. Section) /
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(8 ohms, 20 Hz to 20 kHz, 0.019 % THD)
[A-S500]  .............................................................. 85 W + 85 W
[A-S300]  .............................................................. 60 W + 60 W
(6 ohms, 20 Hz to 20 kHz, 0.038 % THD)
[A-S500] (U, C, R, T, A, B, G models)  .......... 100 W + 100 W
[A-S300] (U, C, R, T, A, B, G, J models)  .......... 70 W + 70 W
Dynamic Power Per Channel / 
¼ ÆÛ¿«Íë” (IHF)
(8/6/4/2 ohms)
[A-S500]  ..................................................... 130/150/185/220 W
[A-S300]  ..................................................... 100/120/140/150 W
MAX Power Per Channel

[B, G models] 
(1 kHz, 0.7 % THD, 4 ohms)
[A-S500]  ..........................................................................120 W
[A-S300]  ............................................................................95 W
IEC Power [B, G models]
(1 kHz, 0.019 % THD, 8 ohms)
[A-S500]  ..........................................................................100 W
[A-S300]  ............................................................................75 W
Power Band Width / 
Íë”ÌïÅ
[A-S500] (0.06 % THD, 42.5 W, 8 ohms)  ........ 10 Hz to 50 kHz
[A-S300] (0.06 % THD, 30 W, 8 ohms)  ........... 10 Hz to 50 kHz
Damping Factor / 
 (SPEAKER-A)
1 kHz, 8 ohms ......................................................... 240 or more
Maximum Effective Output Power / 
î;7G	Z— (JEITA)
(1 kHz, 10 % THD) 
[A-S500]
R, T, L models (8 ohms)  ................................................130 W
R, T models (6 ohms)  ....................................................150 W
[A-S300]
R, T, L, J models (8 ohms)  ............................................100 W
R, T, J models (6 ohms)  ................................................110 W
Input Sensitivity/Input Impedance

/
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PHONO (MM)  .............................................. 3.0 mV / 47 k-ohms
CD, etc.  ...................................................... 200 mV / 47 k-ohms
Maximum Input Signal / 
 (1

kHz) 
PHONO (MM) (0.003 % THD)   ...........................60 mV or more
CD, etc. (0.5 % THD)  ...........................................2.2 V or more
Output Level/Output Impedance /
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REC OUT  .......................................200 mV / 1.0 k-ohms or less
Headphone Jack Rated Output/Impedance /
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CD, etc.

(Input, 1 kHz, 200 mV, 8 ohms)
[A-S500]  .................................................... 430 mV / 470 ohms
[A-S300]  .................................................... 360 mV / 470 ohms
Frequency Response / 
	*þ
:›
Q
CD, etc. (20 Hz to 20 kHz)  ........................................0 ±0.5 dB
CD, etc. Pure DIRECT ON (10 Hz to 100 kHz)  .........0 ±1.0 dB
RIAA Equalization Deviation / 
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PHONO (MM)  ................................................................. ±0.5 dB
Total Harmonic Distortion / 

¶ôÐþêp (20 Hz to 20 kHz)
PHONO (MM) to REC OUT (3 V)  ..................... 0.025 % or less
[A-S500]
CD, etc. to SP OUT (42.5 W, 8 ohms)
  .......................................................................0.015 % or less
[A-S300]
CD, etc. to SP OUT (30 W, 8 ohms)
  ..................................................................... 0.015 % or less
Signal to Noise Ratio / 
	ôø0v;
z (IHF-A Network)
PHONO (MM) (5 mV Input shorted)  ................... 88 dB or more
CD, etc. (Pure DIRECT ON) (200 mV input shorted)
 ............................................................................ 100 dB or more
A-S500A-S300A-S500A-S300 
						

							10
A-S500/A-S300
A-S500/A-S300
• DIMENSIONS / 

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Residual Noise / 
’yÊ ¶ (IHF-A Network)
 .............................................................................................30  μV
Channel Separation / 
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CD, etc. (Input 5.1 k-ohms shorted)
1

kHz  ................................................................. 65 dB or more
10

kHz  ............................................................... 50 dB or more
Tone Control Characteristics / 
Ä”ï¯ïÄé”ç›
Q
BASS
Boost/Cut (50 Hz) ............................................................... ±10 dB
Turnover frequency  ............................................................. 350 Hz
TREBLE
Boost/Cut (20 kHz)  ............................................................. ±10 dB
Turnover frequency  ............................................................ 3.5 kHz
Continuous Loudness Control /
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Attenuation / 
7G4
Yp (1 kHz)  ............................................-30 dB
Gain Tracking Error / 
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