DD-55 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.
Power Consumption 16 W (when using PA-5C power adaptor) Power Supply Adaptor: DC12V (Yamaha PA-5C sold separately) Batteries: Six “C” size, R-14(LR14), or equivalent batter-ies (sold separately) Dimensions (WxDxH) 558 x 355 x 174 mm (22” x 14” x 6” 7/8) Weight 3.8 kg (8 Ibs.
DD-55 PANEL LAYOUT Front Panel Pedal 2 Pedal 1 !0 !1 Front Panel q DEMO Button ! 0 SONG Button w CLICK Button !1 TEMPO Button e DISPLAY. !2 START/STOP Button r VOLUME [ ], [ ] Buttons !3 A-B REPEAT Button...
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DD-55 Side Panel L Side Panel R ! 9 @ 0 Side Panel (Left) Side Panel (Right) !9 DC IN 12V (AC Adaptor) Jack @2 MIDI IN Terminal @0 PHONES/OUTPUT Jack @3 MIDI OUT Terminal @ 1 PEDAL 2 Jack...
DD-55 DISASSEMBLY PROCEDURE Lower Case Assembly (Time required: about 2 min) Remove the sixteen (16) screws marked [80]. The lower case assembly can then be removed. (Fig. 1) Lower Case [80] Lower Case Lower Case Screw Screw In this operation, screw an easily touch and scratch the bottom case, so be careful that screws do not contact it.
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DD-55 Speaker R Upper Case [130] Speaker L [135] [135] [130] [130]: Binding Head Tapping Screw-B 3.0X8 MFZN2Y (EP600250) [135]: Binding Head Tapping Screw-B 4.0X8 MFZN2Y (EP640410) (Fig. 6) Pad Assembly Pad Assembly (Time required: about 5 min) Remove the lower case assembly. (See procedure 1.) Remove the DD 2/2 circuit board.
DD-55 LSI PIN DISCRIPTION HG73C205AFD (XU947C00) SWX00B TONEGENERATOR DD 1/2: IC100 NAME FUNCTION NAME FUNCTION Initial clear CMA3 RFCLKI PLL Clock CMA8 Program address bus PLL Control CMA2 AVDD_PLL Power supply read signal AVSS_PLL Ground CMA1 Program address bus MODE0...
DD-55 uPD63200GS (XM145A00) DAC (Digital to Analog Converter) DD 1/2: IC500 NAME FUNCTION NAME FUNCTION 4/8F 4/8 Fs selection R. REF Channel R voltage reference D. GND Digital ground L. REF Channel L voltage reference 16 BIT 16 bit/18 bit selection L.
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DD-55 DD 1/2 Circuit Board (Component Side) A’ to DD 2/2 CN460 Component Side DD 1/2: 2NA-V707790...
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DD-55 to Battery to Speaker L, R A’ Component Side DD 1/2: 2NA-V707790...
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DD-55 DD 1/2 Circuit Board (Pattern Side) PAD 1 PAD 2 DEMO CLOCK DRUM1 DRUM2 HAND PERC BREAK /TAP START /STOP REPEAT Pattern Side A’ DD 1/2: 2NA-V707790...
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DD-55 PAD 3 PAD 4 PAD 5 PAD 6 PAD 7 VOLUME DRUM2 DRUM3 BACKING SONG TEMPO STANDBY/ON Pattern Side A’ DD 1/2: 2NA-V707790...
DD-55 TEST PROGRAM Setting Conditions Requirements for Measurement Before starting to measure the unit, make sure you have the following instrumentations and test jigs: Measuring instruments: Oscilloscope (Input impedance, 1M Ω or more; Loading, 33 Ω) Level indicator (JIS-C curve; Input impedance, 1M Ω or more; Loading, 33 Ω; 0dBm: 1mW 600 Ω)
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DD-55 Test Items Test No. LED display Test function and judgment criteria 001: Version Displays version for ROM. ROM versions are displayed alternately in the LED. [Displaying the test result] OK, X'XX: ["XX"] NG: ["Err"] 002: Rom Check 1 Checks the ROM.
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DD-55 030: Pad Check Checks the PAD. When a pad is tapped, the LED's indicate its identification number and tapping power. [Displaying the test result] Maximum data: 7F Minimum data: 18 031: Pedal 1 Check Checks the [PEDAL 1]. Connect the pedal to the [PEDAL 1] jack. When the pedal is stepped on, it sounds in bass drum tones.
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DD-55 Table 1. SW test Item Display Note Display Note A-B REPEAT HI-HAT START/STOP BACKING BRAKE/TAP DEMO SONG CLICK TEMPO HAND PERC. VOLUME BASS VOLUME SNARE DIAL...
DD-55 PARTS LIST CONTENTS OVERALL ASSEMBLY ................... 2 ELECTRICAL PARTS ..................4 Note) DESTINATION ABBREVIATIONS Australian model South African model British model Chinese model Canadian model South-east Asia model German model Taiwan model European model U.S.A. model French model General export model (110V)
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<P.1> DD-55 DD-55 OVERALL CIRCUIT DIAGRAM (DD 1/2, DD 2/2) FLASH ROM REGULATOR +3.3V RESET SRAM 1M SRAM 1M MIDI IN SWX00B MIDI OUT ANALOG SWITCH PEDAL 2 (SWITCH) PAD 1 SENSOR POWER AMP PAD 2 SENSOR OP AMP PAD 3 SENSOR...