Ensoniq • SD-1
The SD-1 comes from a long line of Ensoniq's evolving TransewaveTM wave-table digital synthesizers. Starting with the ESQ-1, next came the SQ-80 and then the VFX. The VFX was given a sequencer and called the VFX-SD, and that later evolved into the SD-1 (and it eventually led to the Fizmo). The SD-1 allows for PPG-like synthesis using waveform modulation, a sort of wavetable synthesis. This puts it into a unique class of digital synthesizers along with the PPG Wave series and Waldorf Microwave series.
The SD-1 can create all sorts of acoustic, electric, digital, and analog-like sounds. Its piano sound has over 1 MB of 16-bit waveforms to give it a full and rich realistic tone not found on other digital synthesizers of the time. That piano sound was just the beginning of what would become the "Perfect Piano" used in E-mu/Ensoniq's Halo keyboard and the "Sounds of the ZR" ROM expansion soundset.
The SD-1 has 21 voices of polyphony just like its predecessor, the VFX. A single patch can contain up to 6 of the 168 waves in its ROM memory that can be combined and layered. Advanced and analog-like synth parameters including its dual multi-mode digital filters, three 11-stage envelopes, LFO, and 15 modulation sources allow you to further shape and morph your sounds. There's even a built-in 24-bit VLSI dual effects processor with reverb, chorus, flanging, and delay. The SD-1 also has a standard 61-note keyboard with velocity and aftertouch sensitivity and full MIDI implementation with 12 channels for multitimbral functions as well as four 16-bit DAC outputs.
Like the VFX-SD, the SD-1 has a professional quality on-board sequencer making it a complete all-in-one music production workstation. This is a 24-track sequencer with 25,000 note capacity and it holds up to 60 sequences and 20 songs. There is quantization (96 ppqn), real-time or step entry, looped or linear mode, and auto-punch in/out. Tracks can be set to control the SD-1's internal voices or external MIDI equipment, or both at the same time! An on-board 3.5" disk drive allows you to store your programs sequences, songs, and even MIDI SysEx data. The SD-1 is compatible with all VFX and VFX-SD program librarys too. An optional SQX-70 Sequencer Expander upgrades the sequencer memory from 25,000 to over 75,000 notes.
Called the SD-1 32 Voice.