The Yamaha CS-80 is an analog synthesizer introduced by Yamaha Corporation in 1977. It supports true 8-voice polyphony, with two independent synthesizer layers per voice each with its own set of front panel controls, in addition to a number of hardwired preset voice settings and four parameter settings stores based on banks of subminiature potentiometers (rather than the digital programmable presets featured on the Prophet-5 introduced soon after). It has exceptionally complete performer expression features, such as a layered keyboard that was both velocity-sensitive (like a piano's) and pressure-sensitive ("after-touch") but unlike most modern keyboards the aftertouch could be applied to individual voices rather than in common, and a ribbon controller allowing for polyphonic pitch-bends and glissandos. Production of the instrument ceased in 1980. Vying with the Sequential Circuits Prophet-5 and Oberheim OB-X polysynths for the title, the CS-80 is often described as the pre-eminent polyphonic analog synthesizer, and, together with the monophonic Moog modular synthesizer, commands amongst the highest resale price of any synthesizer.