In the field of electronic music, a sequencer was originally any device that recorded and played back a sequence of control information for an electronic musical instrument. Nowadays the term refers almost always to computer software for recording, playing back and editing MIDI and/or audio data.
Early analog music sequencers used control voltage/trigger interface, but were replaced by digital hardware- or software-based MIDI sequencers, which play back MIDI events and MIDI control information at a specified number of beats per minute. As computer speeds increased in the 1990s, audio editing was added.
Most sequencers now handle both MIDI and audio. Many have numerous further features such as sample playback, effects, and limited music notation. (For software designed specifically for music notation, see Scorewriter.)
Though the term 'sequencer' is today used primarily for software, some hardware synthesizers and almost all music workstations include a built-in MIDI sequencer. There are also standalone hardware MIDI sequencers, such as the Yamaha QY700.
The main sequencers in use are:
- Digital Performer
- Emagic Logic (now owned by Apple)
- Digidesign ProTools
- Cakewalk range of software (e.g. Sonar)
- Steinberg Cubase range
Other sequencers include:
- Ableton Live
- FL Studio
- MusE (not to be confused with MuSE, the streaming audio engine)
- Propellerhead Reason
- Acid Pro 5 (For Win2k and Win XP Pro)