■ Pad General Midi Digital Drum System with 7 pads that respond to velocity (output also to midi velocity)
Sound generation is plain PCM rompler based on YM SWX00B TONEGENERATOR with 2 stereo speakers

■ Basically you just have to hit the pads (you can set individual sensibility, and pedals can be hooked for hihat and kick control). You can assign any of the sounds to any pads and set some effects like reverb , chorus  or special DSP with modulation, tremolo, delay, gate, phaser and ore (these can be set also by Midi)

■ each sound can be volume set as the metronome (32 to 280 BPM or external clock by midi) 

■ The DD-55’s song accompaniment consists of 4 tracks: Drum tracks 1, 2, and 3, and the Backing
track with breaks and fills.

■ A special GM set is implement to follow some song for practice drumming with limited sounds like piano, bass.

■7 Touch-Sensitive Drum Pads (125mm x 4, 88mm x 3),

■Maximum Polyphony 32

■Drum Kits
45 Preset +1 Custom
Songs 100
Tracks 4 (DRUM 1/DRUM 2/DRUM 3/BACKING)
Custom Song 1 Song (approximately 20,000 notes)

■Voices Drum Voices 192 + GM Voices 128 + Drum Kits 8

■Functions Track ON/OFF, TAP START, BREAK, A-B REPEAT,DEMO

■Panel Controls
[STANDBY ON / OFF] switch, [PAD] button, [KIT] button, [SONG] button, [TEMPO] button, VOLUME [ ],
[ ]buttons, [HAND PERC] button, TRACK (DRUM 1 / DRUM 2 /DRUM 3 / BACKING) button, [DEMO]
button, [CLICK] but-ton, [START/STOP] button, [A-B REPEAT] button, [BREAK/TAP] button, [REC] button,
DIAL

■LED (numeric) Display Song / Drum Kit / Tempo etc.

■Auxiliary jacks DC IN12 V, PHONES / OUTPUT, MIDI IN / OUT, PEDAL 1/2
Ouput Impedance 33Ω (PHONES / OUTPUT jack)

■Main Amplifier 5W + 5W (EIAJ) Speaker 8 cm x 2

■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. 6 oz)

■Supplied Accessories
Drum Stick x 2, Foot Pedal 1 & 2, Owner’s Manual

■Optional Accessories Headphones HPE-150

■Some IC: uPD63200GS (XM145A00) DAC

■ USER MANUAL DOWNLOAD

■ SERVICE MANUAL DOWNLOAD

TEST MODE: Set the [STANDBY/ON] switch to ON with the [TEMPO] and [HANDPERC] button pressed and held

Before starting to measure the unit, make sure you have the following instrumentation 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)

A. Setting Conditions
Set the [STANDBY/ON] switch to ON with the [TEMPO] and [HANDPERC] button pressed and held (Fig. 1).
B. Test Entry
To scroll the test items, press the [VOLUME ] button for forwards, and the
[VOLUME ] for backwards.
To start a test, press the [START/STOP] button.
Pressing the [START/STOP] button again returns to the selected item.
If you pass the test and return to the selected item, a dot appears on the upper left
of the LED segment (See Fig.2).
If you fail the test, the LED shows “Err” (See Fig.3). To return to the selected
item, press the [DEMO] button. (Note that the [START/STOP] button is inactive
at this time.)
* Even if the test has successfully completed, pressing the [DEMO] button forces
the system back to the Item Selection.
* The LED displays, and/or the interactions for OK/NG may be different depending
on the test types. For details, see each test item you want to perform.