From SDIY wiki
Music sequencers can be roughly categorized by the type of data they produce, and may refer to:
- Analog sequencers, output CV/Gate control signals and may also support the DIN sync interface. Are more for hands on control in composing or live performance.
- Digital sequencers, implemented in hardware and/or software and can have various outputs. These enable an algorithmic level of control.
- MIDI sequencers, send MIDI signals. These are found implemented both in hardware and software. Some MIDI sequencers also offer CV/Gate and DIN sync interfacing.
- Gate or Step sequencers, play patterns of single notes or concurrent patterns of single notes. See also Drum machine and Groovebox.