A music production synthesizer using Transwave wavetable synthesis, built around dynamic sound morphing and sequencing.
Overview
It is a polyphonic digital additive synthesizer with sequencing built in. The SD-1 has deep modulation: 15 modulation sources and three 11-stage envelopes. One user reported using the instrument since 1991, so it was in studios by that year.
Specifications
| Polyphony | 21 voices (or 32 voices in the SD-1/32) |
| Synthesis type | Transwave® wavetable digital synthesizer |
| Sound engine | Polyphonic Digital Additive Synthesiser & Sequencer |
| Filters | dual multi-mode digital filters |
| Envelopes | three 11-stage envelopes |
| LFO | LFO |
| Modulation sources | 15 modulation sources |
| Original price | $2695.00 |
Design
The SD-1 uses Transwave technology, which morphs the sound by scanning through a wavetable. It is a full music production station with advanced, analog-like synth parameters, and it leans hard on real-time modulation and sequencing. The unit has a floppy disk drive, and the drive is documented to fail. One owner reported that it broke down in 1992 and was replaced.
Context
The SD-1 belongs to Ensoniq's line of Transwave wavetable synthesizers and follows earlier models in the series. It was positioned as a high-end workstation, noted for its powerful MIDI implementation and sequencing. A two-tape VHS video manual was published to support users, which says something about how complex the machine was and who it was aimed at.
Market
One owner bought an SD-1 for $30 planning to repair it, so units may turn up in non-working condition. Original accessories include system disks and a printed manual, and a VHS video manual was also produced. A software emulation of the SD-1/32 is available as a free open-source VST/AU plugin.
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