Yamaha TG-33
FM Vector synth with sound-morphing capabilities, and multi-timbral functionality.
The Yamaha TG-33 Tone Module, released circa 1990, features a unique yet very powerful sound generation method. It is a hybrid between Vector and FM (Frequency Modulation) Synthesis types. Vector Synthesis allows the smooth morphing between two to four sounds via a joystick controller. 4 operators (sound sources) can be combined per program. The value has gone up on these secret bits of kit. Their market value today is around $170-250.