Yamaha AX-596 Service manual

AX-596

STEREO AMPLIFIER

AX-596

SERVICE MANUAL

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 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 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 specifications 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 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

SPECIFICATIONS.......................................................... 1

TO SERVICE PERSONNEL .......................................... 2

IMPEDANCE SELECTOR ............................................. 2

REAR PANELS .............................................................. 3

INTERNAL VIEW ........................................................... 5

DISASSEMBLY PROCEDURES ................................... 5

ADJUSTMENTS ............................................................. 6

IMPORTANT NOTICE

AX-596

BLOCK DIAGRAM......................................................... 6

µ-COM DATA ................................................................. 7

PRINTED CIRCUIT BOARD .................................... 8~15

SCHEMATIC DIAGRAM ........................................ 16~17

PARTS LIST........................................................... 18~27

REMOTE CONTROL TRANSMITTER ........................ 28

100717

AX-596

■ SPECIFICATIONS

■ Power Section

Minimum RMS Output Power

8Ω, 20Hz to 20kHz, 0.015% THD 100W + 100W

Maximum Output Power (EIAJ)

1kHz, 10% THD
8Ω/6Ω 145W / 170W

Dynamic Power (IHF)

8/6/4/2Ω 140/170/220/290W

DIN Standard Output Power

4Ω, 1kHz, 0.7% THD 150W

IEC Output Power

8Ω, 1kHz, 0.015% THD 110W

Power Band Width

8Ω, 50W, 0.03% THD 10Hz to 50kHz

Damping Factor

8Ω, 20Hz to 20kHz 320

Frequency Response

20Hz to 20kHz 0 ±0.5dB
20Hz to 100kHz 0 +0.5, –3dB

Total Harmonic Distortion (20Hz to 20kHz)

CD/DVD to SP OUT (8Ω, 50W) 0.008%

Signal to Noise Ratio (IHF-A-Network)

CD/DVD (Input Shorted, CD/DVD DIRECT AMP ON) 110dB
PHONO (Input Shorted) 92dB

Residual Noise (IHF-A-Network)

CD/DVD DIRECT AMP ON 35µV

■ Control Section
Input Sensitivity / Impedance

CD/DVD etc. 150mV / 47kΩ
PHONO 2.5mV / 47kΩ

Output Level / Impedance

PRE OUT 1V / 1.2kΩ
REC OUT 150mV / 0.6kΩ

Headphone Jack Rated Output / Impedance

0.33V / 680Ω

Channel Separation

CD/DVD (Input 5.1kΩ Terminated) 1kHz/10kHz 65 / 50dB

Tone Control Characteristics

BASS ±10dB (20Hz)
TREBLE ±10dB (20kHz)

Continuous Loudness Control

Attenuation –30dB (1kHz)

■ General
Power Supply

U, C models AC120V, 60Hz
B, G models AC230V, 50Hz
A model AC240V, 50Hz
R, T models AC110/120/220/240V, 50/60Hz

Power Consumption

Approx. 220W

AC Outlets

3 switched outlets
U, C, G, R, T models 100W max, total
1 switched outlets
A, B models 100W max, total

Dimensions (W x H x D) 435 x 151 x 396mm

(17-1/8" x 5-15/16" x 15-9/16")

Weight

11.0 kg (23lbs. 5oz.)

Accessories

Remote Control Transmitter

Batteries

Color

Gold / Black / Titan

* Specifications subject to change without notice.

U ........ U.S.A. model C .... Canada model

G........ European model B .... British model

A ........ Australia model T ..... China model

R ........ General model

• DIMENSIONS

1

AX-596

■ TO SERVICE PERSONNEL

1. Critical Components Information
Components having special characteristics are marked s
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 ohm shunted

by 0.15µF.

● Leakage current must not exceed 0.5mA.

● Be sure to test for leakage with the AC plug in both polarities.

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 WHATSOEVER!

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.

■ IMPEDANCE SELECTOR

2

AX-596

■ REAR PANELS

U model

C model

R model

A model

3

B model

G model

AX-596

T model

J model

4

AX-596

■ INTERNAL VIEW

1 MAIN P.C.B. (9)
2 MAIN P.C.B. (2)
3 MAIN P.C.B. (1)
4 MAIN P.C.B. (5)
5 FUNCTION P.C.B. (13)
6 FUNCTION P.C.B. (4)
7 FUNCTION P.C.B. (5)
8 MAIN P.C.B. (10)
9 MAIN P.C.B. (11)
0 FUNCTION P.C.B. (7)
A FUNCTION P.C.B. (6)
B FUNCTION P.C.B. (3)
C FUNCTION P.C.B. (1)

■ DISASSEMBLY PROCEDURES

(Remove parts in the order as numbered.)
Disconnect the power cord from the AC outlet.

1. Removal of Top Cover

a. Remove 6 screws (1) in Fig. 1.

2. Removal of Front Panel

a. Remove 6 screws (2) in Fig. 1.

3. Removal of Sub Chassis

a. Remove 4 plastic rivets (3) in Fig. 1, then remove the Side Plates.
b. Remove 5 screws (4) in Fig. 1.

4. Removal of Power Transformer

a. Remove 4 screws (5) in Fig. 1.
b. Remove 4 screws (6) in Fig. 1.

5. Checking and Parts Replacement of MAIN P.C.B. (1)

a. Remove 2 plastic rivets (7) in Fig. 1.
b. Remove 12 screws (8) in Fig. 1, then remove the MAIN P.C.B. (1) with

Heat Sink.

Fig. 1

5

■ ADJUSTMENTS

Confirmation of Idling Current

Right after Power is switched ON, confirm the voltages

•

measured at R111, R135 (L ch) and R112, R136 (R ch)
are between 0.4mV to 8.0mV.
If it exceeds 8.0mV, open (cut off) R175 (L ch), R176 (R

•

ch) and reconfirm the voltage.

AX-596

■ BLOCK DIAGRAM

6

AX-596

■ µ-COM DATA

IC308 : M34748E8SP

7