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Roland U20




roland u20

info Country: Japan
Weight: 10 Kg
Dimensions: 98,5 (w) x 31 (h) x 9 (d) cm
audio demo trend price : 150€
manual factory patches demo video comments

Roland U-20
RS PCM Keyboard (1989)


Revamped U110 module with same engine: keyboard version with larger wavetable and better DACs.


main u20

info KEYBOARD 61 velocity keys with aftertouch.
The main panel features a 24 X 2 backlit display, 42 buttons, 3 sliders and a pitchbender & modulation joystick.

Back panel terminal connectors :
- headphones
- main signal out
- aux out (only dry)
- Midi interface
- Pedal expression input (EV-5 or EV-10)
- Pedal switch input for sound hold function (DP-2 or DP-6)
- 2 slots for PCM and data cards more info.

edit TECH
system based on a Intel P8098 CPU which handles 30 voices polyphonic subtractive synthesis RS PCM Resynthesized Pulse Code Modulation.
RS concept resynthesizes and rebuilds new harmonics using a custom sample interpolation, but it lacks a filter structure in fact RS can be mistaken with older L.A synthesis implemented in Roland D50 model.

sound hierarchy is a bit confusing: the lowest level is a tone which is composed by either 1 or 2 samples (2 samples tone reduces the whole polyphony) out of 128 tones available (drum is apart) with no possible edit. The upper level is the timbre composed by a single tone that has some editable parameters: volume, detune and vibrato LFO.
Finally 6 timbres make a patch for performance.

cpu u220

WAVETABLE Pure rompler synth: 3MB ROM (6X 512 kb ROM) is organized in 2 sound groups:

1- acoustic samples eg: piano, bell, guitar, string, organ, brass [...]
2- precalculated basic waveforms eg: pulse, saw and generated harmonics.

demo Hear the PIANO PCM

PERFORMANCE synth manages up to 6 timbres (+ 1 drum part) and individual settings:
- split zones
- stereo panning position
- volume gain
- voice priority
- analog out routing
- aftertouch which can be assigned to LFO, pitch and volume.

roland u20 spec



edit ENVELOPE a single 4-stages amplitude EG.


edit LFO modulates only the amplitude with variable depth, delay time and 9 shapes: triangle, sinewave, square, saw up, saw down, trill (x2) and random (x2).
Special AUTOBEND function is a basic modulation for a pitch-warp effect, so it should be considered as another simpler LFO.

vibrato LFo

there are 2 main FX sections with limited edit parameters:
- reverb: 9 presets including hall, delay, room and gate
- chorus: 5 presets including chorus, flanger and delay.


& CHORD PLAY a basic arpeggiator system with no sync Midi clock: up / down / updown / random.
A chord can be assigned to each key, allowing you to play chords with a single finger. Since a different chord can be assigned to each key C, C# - B, you can perform using diatonic chords or harmonies in thirds. Up to 8 sets of chords can be stored in the U-20 (diatonic, Sus 4, octave, power)


MAINTENANCE and REPAIR there are 2 common reported time issues worth to check out:

- tact switch may need cleanig or direct replacement (better solution)
- dead keys (TUTORIAL)

red glues problem resin

u20 repiar

roland u20 repair
(upper) contact strip

edit MEMORY:
- 64 patches
- 64 performances
- 4 rhythm sets.
RAM is doubled if RAM card model Roland m-256 is fitted.

roland u20 battery


EXPANSION the ROM can be expanded using special PCM cards.
Here's the list of available models:


SN-U110-01 Pipe Organs & Harpsichords INFO
SN-U110-02 Latin and FX Percussion INFO
SN-U110-03 Ethnic INFO
SN-U110-04: Electric Grand and Clavi INFO
SN-U110-05: Orchestral Strings INFO
SN-U110-06: Orchestral Winds INFO
SN-U110-07: Electric Guitar INFO
SN-U110-08: Synthesizer INFO
SN-U110-09: Guitar and Keyboards INFO
SN-U110-10: Rock Drums INFO
SN-U110-11: Sound Effects INFO
SN-U110-12: Sax & Trombone INFO
SN-U110-13: Super Strings INFO
SN-U110-14: Super Ac Guitar INFO
SN-U110-15: Super Brass INFO
Musitronics Akkordeon (ID: 25)  
Musitronics Analog Synthesizer  
Musitronics Voices (ID: 22)  
Musitronics Eldek (ID: 21)  


edit U-20 EDITOR here is a list of available software editors for the synth:
- U20 patch editor (PC freeware ) PIC
- Sounddiver (out of business)
- LIB-220 (PC Sharewave) PIC
- Motu Unisyn (MAC commercial)
- Patchmeister (Amiga) PIC
- U220 / U20 editor - (Atari ST ) PIC)
- Soundquest (MAC/PC commercial) pic below

roland u20 editor


u family

U110- first model, noisier circuit but more PCM slots card- also smaller internal ROM.

U220- more or less the U20 rackmount version



effet VST PLUGIN / SAMPLED VERSION there are some free and commercial samples set:

  name price demo
U110 sample pack Martin 78 FREE
drum sample pack


demo classic strings
demo sweet bells
demo ambient works
demo other strings
demo U20 arpeggiator
demo square waveforms
demo moments of...
demo Hammond RIFF
demo deep choirs
demo mellow rhodes
demo bass sequence
demo U20 factory song
demo U220 factory songs
demo U110 factory songs



Proved Roland U20 various sounds U20 original music U20
test various sounds original music



Company: Roland
Model: U-20
Class: Synthesizer
Keyboard: 61 keys
Dates: 1989
Price: 150€
Synthesis: PCM rompler
Wavetable: 3 mb Rom
Polyphony: 30 voices
Multitimbric: 6 parts
LFO: 1

Memory: 64 slots
Demo: 14







Press PART and RHYTHM simultaneously to enter ROM play mode, hold MARK and JUMP, press ENTER to enter Test mode, While holding JUMP, press NUMBER .ENTER,VALUE [^] to confirm. Hold MARK and JUMP, press EXIT



- free samples set
- More demo



u20 script


thumb u110
edit original brochure


edit original brochure


edit original advert


edit original brochure


u20 script

Roland U-20 FOR SALE

Roland U-20 FOR SALE



u20 script

motherboard logo main intel cpu

Classic digital obsolete friend


REVIEW"U20 sounds are now a bit old, but for some reasons, I still know many people really attached to U20.
A classic early digital keyboard."

manual manual
-affordable -waveforms
-some sounds are still classic
-no filter
-synthesis functions - limited edit

"Thank you for purchasing the U20 RS PCM keyboard. The U20 contains high-quality digital sounds, and can be used as a multi-timral sound generator. It also functions as a Midi keyboard controller" MANUAL

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ROLAND U20 2.5 out of 5 based on 11 ratings. price €100