The Yamaha SY85 was a digital music workstation introduced in 1992. The SY85 differed from other Yamaha synthesizers at the time in that it did not use FM_synthesis as did the other contemporary synthesizers from Yamaha like the SY77 and the SY99 or popular predecessors like the DX7. Instead, its sounds were based on samples, which could be layered and modified to create new sounds.
The workstation featured a 61-note velocity-sensitive keyboard with aftertouch, a double density 3.5" floppy drive, an LCD display, and a nine-track MIDI sequencer. It was a multitimbral synthesizer with 30-note polyphony and full MIDI capabilities. In addition to pitch and modulation wheels, the SY85 featured eight continuous sliders that could be used to adjust various settings in real time. These sliders also functioned as faders when using the built-in sequencer. The SY85 featured two independent effects units which could be run in series or in parallel.
The SY85's internal voice memory could hold 256 voices. These could be played individually or layered, up to four at a time. The keyboard could be split to allow different voices or combinations of voices to be played only in particular regions. Up to 128 of these layered combinations could be stored in internal memory as 'performances'. The SY85 also featured velocity switching, the ability to switch between two samples based on the speed with which a key was depressed. Voices could also be treated with a variety of filters, including a high-pass filter, low-pass filter, band-pass filter, and a band-elimination/band-stop filter.
The sequencer featured eight standard tracks and a dedicated rhythm track. The tracks could be recorded in real or step time and quantized to 1/4, 1/6, 1/8, 1/12, 1/16, 1/24, and 1/32 values. The rhythm track was composed by combining any of 100 rhythm patterns, each of which could be edited independently. These patterns, however, were shared between songs. So changing a pattern would, for good or bad, change it in any song that used it. The sequencer could store up to ten songs (20,000 notes, total) at a time.
Voice and sequencer data could be loaded from or saved to 3.5" double-density floppy discs. Voices and performance combinations could also be loaded from or saved to Yamaha's proprietary MCD64 (64K RAM memory cards (one slot for such cards was provided, alongside one slot for a PCM 'waveform' ROM card). Yamaha and other manufacturers sold expansion sounds for the SY85 in both formats.
As standard, 0.5MB of user waveform RAM was provided, which was expandable up to 3.5MB.
Yamaha also offered a rack-mount version of the SY85 called the TG500. It lacked the sequencer, floppy drive and continuous sliders but added a further card slot of each kind (for four slots in total) and an additional 2MB of internal ROM waveforms for a total of 8MB over the 6MB of the SY85. The TG500 lacked the waveform RAM of the SY85, but could be expanded with up to 1MB of non-volatile waveform RAM. It also featured 64 note polyphony, being one of the first commercial synthesisers to do so.