The Chroma was developed by ARP but the company was forced to shut down before releasing it. Fender took over the project and released it as the Rhodes Chroma. It was one of the first synths to feature touch-buttons and a general value slider instead of pots/faders for every parameter - a concept also popularized by the Yamaha DX7. The Chroma had 16 voice polyphony and also featured a velocity sensitive keyboard.
Famous users include Jethro Tull, Herbie Hancock, Joe Zawinul and Oscar Peterson.