Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The JD-800 was a digital synthesizer released by Roland in 1991. The synthesizer featured many knobs and sliders for patch editing and performance control - features which some manufacturers, including Roland, had been omitting in the name of 'streamlining' since the inception of Yamaha's DX-7. The JD-800 became very popular with musicians who wished to take a 'hands on' approach to patch programming.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.