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Yamaha SY77 is a 16 voice multitimbral music workstation first produced by Yamaha Corporation in 1989. The SY77 is a synthesizer whose architecture combines AFM (Advanced Frequency Modulation) synthesis, AWM2 (Advanced Wave Memory 2) for ROM-borne sample-based synthesis, and the combination of these two methods christened Realtime Convolution and Modulation Synthesis (RCM). The same technology was also packaged in a rack-mounted module released simultaneously, the TG77.
The SY77 is equipped with a 61-key keyboard with velocity and aftertouch; has a pitch wheel and two modulation wheels (the latter being quite a rare feature among keyboards in general); and has a large backlit LCD display, expansion slots, floppy-drive, on-board effects, and a 16,000 note sequencer. Programming is performed through a keypad on the front panel.
When the SY77 was released in late 1989, its initial prices were close to $3000 USD/£2000 GBP. In 1991, it was followed by the SY99, a successor that cost ~$4000/£3000 and expanded its capabilities with a 76-key keyboard, the ability to load user-specified samples for AWM, a more advanced effects unit, and other features.
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