As every tone consists of an almost completely independent synthesizer voice a patch could be considered a layer of up to 4 different synthesizers. The core sampled waveforms and Factory presets of the JD-800 were created by Eric Persing.Ī patch, or single sound, in the JD-800 consists of up to 4 tones. The JD-800 was the first instrument from Roland to have its core sound set of waveforms developed entirely in the United States, under a short-lived branch of Roland's R&D-LA office in Culver City, California. Most of these waveforms are very short and are designed to give character to the attack portion of a sound, while some longer ones are designed for creating pads, or the sustained part of a patch. There are waveforms in a variety of categories, like analog synth, acoustic instruments, like guitars, woodwind, brass and voices. The JD-800 has 108 waveforms built-in, but these can be expanded via PCM-cards.
The JD-800 combines sample playback with digital synthesis, a process that Roland calls Linear Arithmetic synthesis, a technique Roland had been using to great effect in the Roland D-50.
