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IC BLOCK DIAGRAM ................ 22 CIRCUIT BOARDS ................23 INSPECTION ..................33 OVERALL CIRCUIT DIAGRAM This document is printed on chlorine free (ECF) paper with soy ink. PARTS LIST PA 011626 HAMAMATSU, JAPAN EMX66M 20020325-75000 1,387K-2101 Printed in Japan 2002.03 RK88 20020325-2500...
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.
EMX66M SPECIFICATIONS G General specifications 300 W + 300 W/4Ω @0.5% THD at 1 kHz (SPEAKERS OUT A, B) Maximum output power 205 W + 205 W/8Ω @0.5% THD at 1 kHz (SPEAKERS OUT A, B) 600 W/8Ω @0.5% THD at 1 kHz (BRIDGE) 20 Hz–20 kHz +1 dB, –3 dB @1 W output into 8Ω...
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EMX66M G Input specificaitons Input level Actual load Nominal Connector Input connectors impedance impedance Max. before type Nominal level Sensitivity cliping 50–600Ω –62 dB (0.616 mV) –50 dB (2.45 mV) –20 dB (77.5 mV) CH INPUT (Low-Z) Mics 3 kΩ...
EMX66M PANEL LAYOUT G CONTROL PANEL 1. CONTROL SECTION • Channel Control Equalizer (HIGH, MID, LOW) HIGH MONITOR control EFFECT control — 15 LEVEL control PAD switch (CH1-4) — 15 — 15 MONITOR EFFECT LEVEL • Digital Effect EFFECT select switch...
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2TR IN MASTER EFFECT RTN MONITOR • POWER AMP LIMITER indicator POWER AMP POWER AMP select switch LIMITER MAIN MAIN MAIN MAIN BRIDGE • PHANTOM switch, indicator PHANTOM ON/OFF switch, indicator PHANTOM • YAMAHA SPEAKER PROCESSING YAMAHA SPEAKER ON/OFF switchÅ@ PROCESSING...
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EMX66M • POWER switch, indicator POWER ON/OFF switch, indicator power ON / 2. INPUT/OUTPUT SECTION Super Hi-Z LINE INPUT TO MAIN OUT PUT ON / EFFECT OUT Hi-Z Hi-Z Hi-Z Hi-Z EEEngine Low-Z Low-Z Low-Z Low-Z MAIN FOOT SW AUX IN...
EMX66M DISASSEMBLY PROCEDURE Front Panel Assembly (Time required: about 3 min) 1-1. Remove the seven (7) screws marked [80] and the screw marked [90]. (Fig.1) 1-2. Hold volume knobs and pull the panel to the front. (Fig.1) 1-3. Remove the screw marked [100]. The front panel assembly can then be removed.
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EMX66M MIX66 Circuit Board (Time required: about 18 min) 3-1. Remove the front panel assembly. (See Procedure 1) 3-2. Remove the cable from the cord binder marked [240]. (Fig.2) 3-3. Remove the shield case. (See Procedure 2-2) 3-4. Pull out the connector assembly from CN301 on the DSP-ZFX circuit board.
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EMX66M PWR Circuit Board 4/4 (Time required: about 4 min) 4-1. Remove the front panel assembly. (See Procedure 1) 4-2. Pinch slightly the stopper of the power switch escutcheon with a plyer, and pull it to the front to remove. (Fig.7-1) 4-3.
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EMX66M 5-3. Hold the cord holder and pull the rear panel to the front to remove. (Fig.9) Note: When reinstalling, install the rear panel assembly and the front panel assembly in that order to connect the power supply connector easily.
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EMX66M PWR Circuit Board 1/4 (Time required: about 10 min) 8-1. Remove the rear panel assembly. (See Procedure 5) 8-2. Remove the PWR circuit board 2/4. (See Procedure 6) 8-3. Remove the PWR circuit board 3/4. (See Procedure 7) 8-4.
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EMX66M Fan (Time required: about 3 min) 9-1. Remove the rear panel assembly. (See Procedure 5) 9-2. Remove the two (2) screws marked [130]. The fan can then be removed. (Fig.8) Power Transformer (Time required: about 4 min) 10-1. Remove the front panel assembly. (See Procedure 1) 10-2.
EMX66M LSI PIN DESCRIPTION ZFX-2 (XY297A00) CPU DSP-ZFX: IC306 NAME FUNCTION NAME FUNCTION AXLR2 Audio Data Transmitt Unit 2/3 Left and Right Channel Frame Frequency Signal Audio Data Receive Unit 1 Data Input External Memory and I/O Data Bus Audio Data Receive Unit 2 Data Input...
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EMX66M UPD78082GB-XXX (XY296A00) MCU DSP-ZFX: IC303 NAME FUNCTION NAME FUNCTION P12/ANI2 8 bits input/output port./A/D converter analog input. Not connect. P13/ANI3 8 bits input/output port./A/D converter analog input. Port 3. 8 bits input/output port. P14/ANI4 8 bits input/output port./A/D converter analog input.
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EMX66M MIX66 Circuit Board HIGH HIGH HIGH HIGH HIGH HIGH VOVA VOVA VOVA VOVA MONITOR MONITOR MONITOR MONITOR MONITOR MONITOR EFFECT EFFECT EFFECT EFFECT EFFECT EFFECT LEVEL LEVEL LEVEL LEVEL LEVEL LEVEL Super Hi-Z 1 LINE 1 Super Hi-Z Hi-Z...
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EMX66M MONITOR GRAPHIC EQUALIZER PHAMTOM ON / OFF VOVAL ECHO 1 VOVAL ECHO 2 2TR IN VOVAL REVERB 1 MASTER EFFECT RTN VOVAL REVERB 2 MAIN GRAPHIC POWER AMP EQUALIZER MODE HALL 1 HALL 2 ROOM YAMAHA PLATE SPEAKER AUX IN...
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EMX66M PWR 1/4 Circuit Board to PWR2/4-W101RE2 to PWR2/4-W101BE2 to PWR...
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EMX66M to PWR1/4-W103OR2 to FAN Assembly to PWR2/4-W101BL2 to Power Tranceformer to PWR2/4-W101WH2 Component side 3NA-V826900 1...
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EMX66M PWR 2/4 Circuit Board SPEAKERS BRIDGE to PWR 1/4-W101RE1 to PWR 1/4-W101BE1 to PWR 1/4-W101BL1 to PWR 1/4-W101WH1 Component side PWR 3/4 Circuit Board PWR 4/4 Circuit Board ON / OFF AC IN to PWR 4/4-CN107 to Power Tranceformer...
AUX IN level control: 2TR IN level control: MASTER (MAIN) level control: MONITOR GRAPHIC EQUALIZER (7 band) fader: CENTER EFFECT RTN level control: 2TR IN: MASTER (MAIN) level control: PHANTOM switch: YAMAHA SPEAKER PROCESSING switch: OFF POWER AMP switch: MAIN-MONITOR...
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EMX66M Gain Check On condition of 2.1, confirm that the output level of each terminal meets the table 2.2-1. Table 2.2-1 [unit: dBs] INPUT INPUT LEVEL MAIN OUT(L,R) MONITOR OUT EFFECT OUT REC OUT Low-Z +4±2 +4±2 +4±2 -13.8±2 -32 (PAD ON) Hi-Z +4±2...
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EMX66M LED Meter Check When the output level of MAIN OUT and MONITOR OUT meets the Table 2.6-1, confirm that the corresponding LED meter starts to light up. Table 2.6-1 [unit: dBs] OUTPUT LEVEL +10±2 +7±2 +4±2 -1±2 -6±2.5 Distortion Rate Check On condition of 2.1, set the INPUT and MASTER volume for each terminal to nominal position.
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Apply 70Hz / -26dB signal into input terminal, and confirm that the output level is within 6.5±2dB from the level for 1kHz input with YAMAHA SPEAKERS PROCESSING switch OFF. Besides, confirm that the LED lights up when YAMAHA SPEAKERS PROCESSING switch is ON and that LED goes out when the switch is OFF.
EMX66M 3.1.6 Harmonic Distortion Rate Check Note: This mesurement should be finished in 30 seconds. • Apply 1kHz signal into input terminal, and confirm that output level of 300W/4Ω (33.0dBs) can be gained with harmonic distortion rate less than 0.5%.
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EMX66M For the case that the POWER AMP switch is 'MAIN BRIDGE' 3.2.1 Preparation • POWER AMP switch: MAIN BRIDGE Input • INPUT terminal: CH 5 LINE 1 • MASTER (MAIN): MAX • OUTPUT terminal: BRIDGE 4Ω Level meter Speaker Resistor •...
EMX66M PARTS LIST RACK MOUNT KIT RK-88 CONTENTS OVERALL ASSEMBLY ...................... 2 FRONT PANEL ASSEMBLY ....................4 REAR PANEL ASSEMBLY ....................6 ELECTRICAL PARTS ....................... 8 RK-88 RACK MOUNT KIT ....................26 Note) DESTINATION ABBREVIATIONS Australian model South African model...
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EMX66M DESCRIPTION REMARKS PART NO. QTY RANK REF NO. V 2 4 4 0 2 0 0 R402 Metal Film Resistor 2.4K 1/4 F V 2 4 4 0 2 0 0 R403 Metal Film Resistor 2.4K 1/4 F VV276800 R404 Flame Proof C.