The Ensoniq SD-1 is a digital synthesizer that made a mark in the 1990s for its versatility and powerful sound. Offering a combination of subtractive synthesis and sampled waveforms, the SD-1 produces a wide range of sounds, from atmospheric pads to punchy basses. Its 61-key keyboard is velocity-sensitive, providing enhanced expressiveness. With features such as built-in effects, modulation, and split/layer capabilities, the Ensoniq SD-1 was a favored choice for musicians and producers seeking a versatile workstation.