Music sequencer

A sequencer [ zekvɛntsər ] is an electronic device or a software for recording, playing and editing of data for the creation of music.


Core of a sequencer is the storage and transmission of a score to a tone generator. The score is available in a machine readable format, stating pitch, tone duration and possibly other aspects of the playable notes of one or more votes in order of their time to a device further generates the corresponding tones. Both functions can be combined in one device. As a rule, allows a sequencer, enter notes about suitable methods, eg via the import on a master keyboard or entering notes on the computer. In contrast, a concrete, physical sound image is reproduced electronically in the music.

By recording the notes and their parameters instead of recording the complete mode shapes results in a number of advantages:

  • The data amount of music stored is comparatively small;
  • Transposition and tempo changes are easy to perform;
  • It may have different instruments are controlled with the same data.

The reduction to notes certain aspects can not be played, or only very limited:

  • The sound of individual instruments;
  • The individual expression of a musician.

The sequencer, other information can be controlled as sound. For example, to controller data can be sequenced for example, to control filter EG or other controllable via MIDI Controll numbers events.


The term was coined sequencer in the 1960s as part of the development of electronic music, and referred to an electronic, now mostly digital device or a corresponding software. As a historical precursor of the sequencer to the mechanical musical instruments can be considered mechanically saved the notes of a composition ( eg, on a roller pin ) and passed to the corresponding tone generator.

Since the early 1980s sequencer are mostly known as a MIDI sequencer. With a MIDI sequencer be recorded or played no actual sounds, but only the control data ( MIDI data ) to which a wide variety of tone generator ( synthesizer) can be controlled. The data stored in a MIDI sequencer data contain information about the pitch of individual notes, whose velocity and duration. Furthermore, the sound generation can be instructed what instruments the sounds are played, which is very useful especially in multi-track arrangements. The input of notes may be via a master keyboard in real time or can be entered using an editor, such as on a computer by drawing with a computer mouse.

Step Sequencer

The history of the sequencer starts with analog step sequencer to control the sound generation of synthesizers with adjustable voltages. The name comes from the fact that each sound event step by step ( "step by step " ), with its characteristics such as pitch, duration, etc. programmed. Initially Only 8-64 tones were possible. This type of sequencers produced predominantly repetitive pitch and sound patterns ( "loops ") can be changed during playback. They are a typical stylistic means of electronic music of the Berlin school ( Tangerine Dream, Klaus Schulze ) in the mid- 1970s to the early 1980s. During the rediscovery of analog synthesizer from the early eighties, the call for step sequencers became louder again, since no such more devices were available on the market at this time. Meanwhile, step sequencers are again produced by some, mostly small companies. This is the one to analog devices (without memory option ), but mainly to digital versions with memory and MIDI outputs.

The development of step sequencers are pattern sequencer. These can play multiple step pattern in song structures after the other without interruption.

Early 1980s were popular step sequencer Roland (TB -303, SH -101, MC -202 ) and Casio ( VL -1 Casiotone MT -70, Sampletone SK-1 ) on the market that quickly give way in the music charts found.

MIDI sequencer

The next development was the digitization of the game data, which initially storing them later allowed on audio cassettes and disks. Then the real-time recording followed by directly importing using a keyboard. After 1983 MIDI was introduced as a universal language for electronic musical instruments. Today's sequencer are predominantly apparatus for recording, editing and playback of MIDI data.

This type of sequencers are also known to differentiate the step sequencer as real-time sequencer. For them there is no compelling division of the received mainly via MIDI sound data by pattern or steps. This way you can this sequencer similar to a multi-track tape use as a recording device. At the end of the recordings of all tracks and their possible processing for error correction or arrangement all tracks are then played back and output the contained audio data to the sound generator via midi. The outputs of the tone generator are then taken either on tape or directly on the computer. Nowadays it often accounts for all physical tone generator, because software sound module (VST ) in the computer can produce the sounds.

Sequencer in Tapemachine

With sequencers in Tapemachine control data can be arranged and edited as on a temporal axis. Today, they are the classic work means studio productions, step and pattern sequencer is more often found in the live arena.


Since the mid- 1990s are software solutions available that enable addition to pure MIDI sequencing and hard disk recording and are referred to as MIDI-/Audio-Sequenzer. The functionality has been further enhanced so that a modern MIDI-/Audio-Sequenzer practically represents a complete virtual music studio, with integrated mixer, interfaces for the integration of effects and virtual instruments ( software-based tone generator).

Tracker - Sequencer

In addition to classical music developed in the environment software sequencers, there are also the so-called trackers, which were developed in the mid -1980s in the context of the Amiga. In this computer - environment created with them pieces of music for computer games such as Pinball Dreams or Unreal. In the 1990s, trackers were perceived with the associated file formats from the demo scene and developed. The tracker concept with compact file sizes with good quality of his music has been attractive for the creation of computer demos, which at that time still had to fit on floppy disks. In the 2000s, trackers were, inter alia, used in the electro scene as well as music and sound on mobile devices with limited hardware equipment, such as the Gameboy Advance.

Add a tracker is, in contrast to other sequencers or musical notation, the time course of top-down display (instead of from left to right). The notes are there in a table, with one column specifies the uniform meter. Another difference from other Musiksequenzersoftware is the usual here export to editable formats Tracker instead uneditierbaren in WAV or MP3 files. The technically open accessibility of the source materials and the sequence programming in the tracker formats corresponds conceptually about the open source concept in computer science for program code.

Original file type, the tracker was MOD. Later formats with enhanced properties (eg more channels, compression, etc ) defined, for example, XM, IT, S3M, and many more. The latest variant is the XML -based and is under the GPL XRNS format, introduced with the Renoise Tracker.

Meanwhile, the differences between trackers and other Musiksequenzersoftware are becoming increasingly blurred; for example, presented in 2007, the British Computer Music Magazine tracker in the third generation, such as Renoise or Jeskola Buzz, as a professional and affordable alternative to other music studio software.

A technical overview of current and historical tracker music sequencer can be found on the list of trackers.


Another variation of the sequencer are the so-called Composer or Arranger. These programs combine the capabilities of classical MIDI sequencer with a style- oriented approach. A sequence of harmonies is equipped with various musical styles, the styles, linked. The software composes a piece of music. The harmony sequences are usually entered with chord symbols in the software. Most programs contain a number of different styles of music. However, it can also create your own styles, which can then be used in any number of pieces.

Common programs of this genre are:

  • Jammer Professional
  • Band-in- a-box

On the hardware side, there is also the genus of groove boxes such as:

  • Elektron Monomachine, Machinedrum
  • Korg Electribe, Korg Karma
  • Radikal Technologies Spectralis
  • Roland MC -303, 505, 606, 808, 909
  • Yamaha RM1X

Groove Boxes often claim to be an "all -in -one" production machine. However, this formulation has a slightly exaggerated because you usually can not fully express his creativity through the restriction to such a device.

List of hardware sequencers

  • Akai MPC
  • Doepfer A -155 Sequencer, A- 154 Sequencer Controller, A- 156 Quantizer, Dark Time
  • Genoqs Octopus, Nemo
  • Jazz Mutant Lemur
  • Manikin pacemaker (see picture above)
  • SequentiX P3
  • SequentiX Cirklon
  • Quasimidi Style Drive
  • Electron Oktatrack
  • MIDIbox SEQ

List of software sequencers