Physical modelling is a method of synthesis in which a mathematical model of the instrument being synthesized is used to create the sound. It is the best way of approximating a real instrument....
OB-X
"Oberheim released the polyphonic and programmable OB-X in 1979. Available in four-,
six-, and eight-voice configurations, it offered 32 program memories, polyphonic
portamento, and polyphonic sample-and-hold."