The Roland U-20 is a musical keyboard and rompler released by Roland in 1989. There is also a 1Urackmount version, the U-220. It is the successor to the U-110 rackmount, released in 1988.
The synthesizer engine itself merely plays back stored PCM samples. Such a synthesizer is known as a rompler, as opposed to a sampler, which lets you record and load in custom samples. Nevertheless, sample playback can be slightly customized via editing its ADSR envelope and applying DSP effects.
Thanks to its popularity, there exists dedicated software for editing sound settings from a computer via MIDI connection. There are also hardware presets in programs like Cubase allowing easier communication.
128 different voices (additional may be supplied with ROM/RAM cards)