Music sequencer

A music sequencer (or simply sequencer) is a device or application software that can record, edit, or play back music, by handling note and performance information in several forms, typically CV/Gate, MIDI, or Open Sound Control (OSC), and possibly audio and automation data for DAWs and plug-ins. (See §Types of music sequencer)[note 1]


Modern sequencers

1980s typical software sequencer platform, using Atari Mega ST computer.
Today's typical software sequencer, supporting multitrack audio (DAW) and plug-ins (Steinberg Cubase 6[1])
User interface on Steinberg Cubase v6.0, a digital audio workstation with an integrated software sequencer.

The advent of Musical Instrument Digital Interface (MIDI) and the Atari ST home computer in the 1980s gave programmers the opportunity to design software that could more easily record and play back sequences of notes played or programmed by a musician. This software also improved on the quality of the earlier sequencers which tended to be mechanical sounding and were only able to play back notes of exactly equal duration. Software-based sequencers allowed musicians to program performances that were more expressive and more human. These new sequencers could also be used to control external synthesizers, especially rackmounted sound modules, and it was no longer necessary for each synthesizer to have its own devoted keyboard.

As the technology matured, sequencers gained more features, such as the ability to record multitrack audio. Sequencers used for audio recording are called digital audio workstations (or DAWs).

Many modern sequencers can be used to control virtual instruments implemented as software plug-ins. This allows musicians to replace expensive and cumbersome standalone synthesizers with their software equivalents.

Today the term "sequencer" is often used to describe software. However, hardware sequencers still exist. Workstation keyboards have their own proprietary built-in MIDI sequencers. Drum machines and some older synthesizers have their own step sequencer built in. There are still also standalone hardware MIDI sequencers, although the market demand for those has diminished greatly due to the greater feature set of their software counterparts.

Types of music sequencer

Music sequencers are often categorized by handling data types, as following:.

Also, music sequencer can be categorized by its construction and supporting modes.

Realtime sequencer (realtime recording mode)

A realtime sequencer on the synthesizer

Realtime sequencers record the musical notes in real-time as on audio recorders, and play back musical notes with designated tempo, quantizations, and pitch. For editing, usually "punch in/punch out" feature originated in the tape recording is provided, although it requires enough skills to obtain desired result. For detailed editing, possibly another visual editing modes under graphical user interface may be more suitable. Anyway, this mode provides usability similar to the audio recorder already familiarized by musicians, and it is widely supported on software sequencer, DAW, and built-in hardware sequencers.

Analog sequencer

An analog sequencer

Analog sequencers are typically implemented with analog electronics, and play the musical notes designated by a series of knobs or sliders corresponding to each musical note (step). It is designed for both composition and live performance; users can change the musical notes at any time without regarding recording mode. And also possibly, the time-interval between each musical note (length of each step) can be independently adjustable. Typically, analog sequencer is used to generate the repeated minimalistic phrases which is reminiscent of Tangerine Dream, Giorgio Moroder or trance music.

Step sequencer (step recording mode)

A step rhythm sequencer on the drum machine
A step note sequencer on the bass machine

On the step sequencers, musical notes are rounded into the steps of equal time-interval, and users can enter each musical note without exact timing; Instead, each timing and duration of step are designated in several ways:

In general, step mode, along with roughly quantized semi-realtime mode, is often supported on the analog drum machines, bass machines and several groove machines.

Software sequencer

Software sequencer is a class of application software providing a functionality of music sequencer, and often provided as one feature of the DAW or the integrated music authoring environments. The features provided as sequencers vary widely depending on the software; even an analog sequencer can be simulated. The user may control the software sequencer either by using the graphical user interfaces or a specialized input devices, such as a MIDI controller.

Typical features on software sequencers

Numerical editor on Tracker

Score editor

Piano roll editor
with strip chart

Audio and MIDI tracks on DAW

Loop sequencer

Sample editor
with beat slicer

Vocal editor
for pitch and timing


Early sequencers

See also: Category:Mechanical musical instruments and Music box § Evolving box production
Barrel with pins on a large stationary barrel organ
Music roll
on barrel organ
Player piano (1920) controlled by piano roll.
RCA Mark II (1957),
controlled via wide punched paper roll

The early music sequencers were sound producing devices such as automatic musical instruments, music boxes, mechanical organs, player pianos, and Orchestrions. Player pianos, for example, had much in common with contemporary sequencers. Composers or arrangers transmitted music to piano rolls which were subsequently edited by technicians who prepared the rolls for mass duplication. Eventually consumers were able to purchase these rolls and play them back on their own player pianos.

The origin of automatic musical instruments seems considerably old. As early as the 9th century, Persian inventors Banū Mūsā brothers invented hydropowered organ using exchangeable cylinders with pins,[6] and also automatic flute player using steam power,[7][8] as described on their Book of Ingenious Devices. In the 14th century, rotating cylinder with pins were used to play carillon in Flanders, and at least in the 15th century, barrel organs were seen in the Netherlands.[9]

In the late-18th or early-19th century, as the results of Industrial Revolution, various automatic musical instruments were invented, for examples: music box, barrel organ and barrel piano using barrel / cylinder with pins or metal disc with punched holes; or mechanical organ, player piano and orchestrion using book music / music rolls (piano rolls) with punched holes, etc. These instruments were widely spread as the popular entertainment devices before the inventions of phonograph, radio, and sound film. Amongst of all, especially the punched tape media had been long lived until the mid-20th century: earliest programmable music synthesizers including RCA Mark II Sound Synthesizer in 1957, and Siemens Synthesizer in 1959, were also controlled via punch tapes similar to piano rolls.[10][11][12]

Another inventions were came from sound film technology. The drawn sound technique which appeared in the late 1920s, is notable as a precursor of today's intuitive graphical user interfaces. On this technique, notes and various sound parameters were controlled by hand-drawn waves on the films, resembling piano rolls or strip charts on the modern sequencers/DAWs. It was often utilized on early experiments of electronic music, including Variophone developed by Yevgeny Sholpo in 1930, and Oramics designed by Daphne Oram in 1957, etc.

Analog sequencers

Main article: Analog sequencer
Earliest commercially available analog sequencers (front) on Buchla 100 (1964/1966)[13]
Moog sequencer module (left, probably added after 1968) on Moog Modular (1964)

During the 1940s1960s, Raymond Scott, an American composer of electronic music, invented various kind of music sequencers for his electric compositions. The "Wall of Sound", once covered on the wall of his studio in New York during the 1940s1950s, was an electro-mechanical sequencer to produce rhythmic patterns, consisting of stepping relays (used on dial pulse telephone exchange), solenoids, control switches, and tone circuits with 16 individual oscillators.[14] Later, Robert Moog explained it as "the whole room would go 'clack - clack - clack', and the sounds would come out all over the place".[15] The Circle Machine, developed in 1959, had dimmer bulbs arranged in a ring, and a rotating arm with photocell scanning over the ring, to generate arbitrary waveform. Also, the rotating speed of arm was controlled via brightness of lights, and as the results, arbitrary rhythms were generated.[16]

Clavivox, developed since 1952, was a kind of keyboard synthesizer with sequencer. On its prototype, a theremin manufactured by young Robert Moog was utilized to enable portamento over 3-octave range, and on later version, it was replaced by a pair of photographic film and photocell for controlling the pitch by voltage.[15]

In 1965 Ralph Lundsten had a polyphonic synthesizer with sequencer called Andromatic. built for him by Erkki Kurenniemi.[17]

Step sequencers

Electro-mechanical disc sequencer on early drum machine (1959)
Eko ComputeRhythm (1972),[18][19] one of the earliest programmable drum machines
Firstman SQ-01 (1980),[20] one of the earliest step bass machines
See also: Drum machine and Groovebox

The step sequencers played rigid patterns of notes using a grid of (usually) 16 buttons, or steps, each step being 1/16 of a measure. These patterns of notes were then chained together to form longer compositions. Sequencers of this kind are still in use, mostly built into drum machines and grooveboxes. They are monophonic by nature, although some are multi-timbral, meaning that they can control several different sounds but only play one note on each of those sounds.

Computer music

Main article: Computer music
CSIRAC played the earliest computer music in 1951

On the other hand, software sequencers were continuously utilized since the 1950s in the context of computer music, including computer-played music (software sequencer), computer-composed music (music synthesis), and computer sound generation (sound synthesis). In June 1951, the first computer music Colonel Bogey was played on CSIRAC, Australia's first digital computer.[21][22] In 1956, Lejaren Hiller at the University of Illinois at Urbana-Champaign wrote one of the earliest programs for computer music composition on ILLIAC, and collaborated on the first piece, Illiac Suite for String Quartet, with Leonard Issaction.[23] In 1957 Max Mathews at Bell Labs wrote MUSIC, the first widely used program for sound generation, and a 17-second composition was performed by the IBM 704 computer. Subsequently, computer music was mainly researched on the expensive mainframe computers in computer centers, until the 1970s when minicomputers and then microcomputers became available in this field.

Digital sequencers

EMS Sequencer 256 (1971), a branched product of the Synthi 100

In 1971, Electronic Music Studios (EMS) released one of the first digital sequencer products as a module of Synthi 100, and its derivation, Synthi Sequencer series.[24][25] After then, Oberheim released the DS-2 Digital Sequencer in 1974,[26] and Sequential Circuits released Model 800 in 1977 [27]

Also in 1977, Roland Corporation released their first microprocessor-based digital sequencer, MC-8 Microcomposer, also called computer music composer by Roland.[28] It equipped a keypad to enter notes as numeric codes, 16KB RAM for a maximum of 5200 notes (large at the time), and a polyphony function which allocated multiple pitch CVs to a single Gate.[29] The earliest known user was Yellow Magic Orchestra in 1978.

Software sequencers

Synclavier I (1977)
Fairlight CMI (1979)

In 1975, New England Digital (NED) released ABLE computer (microcomputer)[30] as a dedicated data processing unit for Dartmouth Digital Synthesizer (1973), and based on it, later Synclavier series were developed. The Synclavier I, released in September 1977,[31] was one of the earliest digital music workstation product with multitrack sequencer. Synclavier series evolved throughout the late-1970s to the mid-1980s, and they also established integration of digital-audio and music-sequencer, on their Direct-to-Disk option in 1984, and later Tapeless Studio system.

Page R on Fairlight
Tracker software

In 1980, renewed Fairlight CMI Series II with its sequencer, "Page R", combined step sequencing with sample playback. In 1987, this led to the development of similar software sequencers of this kind, called Trackers, which became popular in the 1980s and 1990s as simple sequencers for creating computer game music, and are yet popular in the demoscene and chiptunes.

Visual timeline of rhythm sequencers

Main articles: Drum machines, Groovebox, and Beat slicing

Mechanical (pre 20c)

Rhythmicon (1930)

Drum machine
(late 1950s)

Transistorized drum machine (mid-1960s)

Step drum machine (1972)

Digital drum machine (1980)

“Page R” on Fairlight (c.1980)

Groove machine (mid-1980s)

Tracker (1987)

Beat slicer (1990s)

Spectrogram editing (1994)

Loop sequencer (1998)

Note manipulation on audio tracks (2009)

See also


  1. On of TechTarget (, an author seems to define a term "Sequencer" as an abbreviation of "MIDI sequencer".
    • Margaret Rouse (April 2005). "Define sequencer". ( TechTarget. In digital audio recording, a sequencer is a program in a computer or stand-alone keyboard unit that puts together a sound sequence from a series (or sequence) of Musical Instrument Digital Interface ( MIDI ) events (operations). The MIDI sequencer allows the user to record and edit a musical performance without using an audio-based input source. ...
  2. Automation parameters on the DAW are often interoperable with MIDI messages (control changes (CC) or SysEx); in that case, it can be controlled in real-time via pre-assigned MIDI messages generated by MIDI controllers or MIDI sequencers, etc. And even more, on the several DAWs, automation parameters are explicitly recorded as MIDI messages on their embedded MIDI sequencers. (See Price 2006)
  3. The term "audio sequencer" seems to be relatively new expression and seems to be not clearly defined, yet. For example, "DAW integrated with MIDI sequencer" is often referred as "Audio and MIDI sequencer". However, in this usage, the term "audio sequencer" is just a synonym for the "DAW", and beyond the scope of this article. In that case, please check Digital audio workstation.


  1. "Cubase 6 screenshot licensed under CC-BY-SA-3.0". Steinberg Media Technologies GmbH.
  2. Rothstein, Joseph (1995). MIDI: A Comprehensive Introduction. Computer Music and Digital Audio Series. 7. A-R Editions, Inc. pp. 77, 122. ISBN 978-0-89579-309-6.
  3. Pinch, Trevor. J.; Trocco, Frank (2009). "Buchla's Box". Analog Days: The Invention and Impact of the Moog Synthesizer (reprint ed.). Harvard University Press. pp. 55–56. ISBN 978-0-674-04216-2.
    "Subotnick suggested that using a light source to control sound might be promising. ... Later he [Buchla] turned this into an electro mechanical sequencer by introducing step relays and a dial. ... Buchla, like Moog, realized that voltage control ... But Buchla was after something different; ... Buchla was led to the electronic sequencera device that later was used to make much influential pop, rock, and dance music. A sequencer produces predetermined control voltages in a cycle or sequence and can endlessly recylce ..."
    Note: for a sequencer using a light source, see "Circle Machine" on #Analog sequencers and Raymond Scott#Electronics and research.
  4. Price, Simon. "Using Mixer Automation In Reason - Reason Tips & Techniques". Technique: Reason Notes. Sound On Sound. No. September 2006.
    "Controller Data Vs. Automation / ... sequencer package such as Logic or Pro Tools, ... are akin to automation on professional hardware mixing consoles, ... This type of automation system is different to using MIDI Continuous Controller [Control Changes] (CC) data, ... In Reason, automation is MIDI Controller [Control Changes] data, but with some specialised tools for handling the data and playing it back. ...",
    "Recording Mixer Automation / As automation in Reason is MIDI CC data, it must be recorded on a sequencer track."
  5. Pejrolo, Andrea (2011). "1.7.1 The Primary Goals You Want to Achieve with Your Audio Sequencer". Creative Sequencing Techniques for Music Production: A Practical Guide to Pro Tools, Logic, Digital Performer, and Cubase. Taylor & Francis. p. 48. ISBN 978-0-240-52216-6. (sub-section title contains the expression "Audio Sequencer")
  6. Fowler, Charles B. (October 1967). "The Museum of Music: A History of Mechanical Instruments". Music Educators Journal. Music Educators Journal. 54 (2): 4549. doi:10.2307/3391092. JSTOR 3391092.
  7. Koetsier, Teun (2001). "On the prehistory of programmable machines: musical automata, looms, calculators". Mechanism and Machine Theory. Elsevier. 36 (5): 589603. doi:10.1016/S0094-114X(01)00005-2.
  8. Banu Musa (authors) (1979). Donald Routledge Hill (translator), ed. The book of ingenious devices (Kitāb al-iyal). Springer. pp. 767. ISBN 9027708339.
  9.  Chisholm, Hugh, ed. (1911). "Barrel-organ". Encyclopædia Britannica (11th ed.). Cambridge University Press.
  10. "The RCA Synthesiser". 120 Years of Electronic Music ( version is available)
  11. "Das Siemens-Studio für elektronische Musik von Alexander Schaaf und Helmut Klein" (in German). Deutsches Museum.
  12. Holmes, Thom (2012). "Early Synthesizers and Experimenters". Electronic and Experimental Music: Technology, Music, and Cluture (4th ed.). Routledge. pp. 190192. ISBN 978-1-136-46895-7. (See also excerpt of pp. 157160 from Holmes 2008)
  13. Holmes, Thom (2008). Electronic and experimental music: technology, music, and culture (3rd ed.). Routledge. p. 222. ISBN 978-0-415-95781-6, ISBN 978-1-135-90617-7. Moog admired Buchla's work, recently stating that Buchla designed a system not only for "making new sounds but [for] making textures out of these sounds by specifying when these sounds could change and how regular those change would be."
  14. "Wall of Sound (sequencer)".
  15. 1 2 Robert Moog. "Memories of Raymond Scott".
  16. "Circle Machine". 2 sound files: Raymond Scott's demonstration, and commercial soundtrack for new batteries of Ford Motors.
  17. Jörgen Städje (2012-10-06). "Andromatic, den automatiska andromedaren". International Data Group (IDG).
  18. "EKO Computerhythm (1972)". Jarrography - The ultimate Jean Michel Jarre discography.
  19. "EKO Computerhythm".
  20. "Multivox International". SYNRISE (in German). Archived from the original on 2003-04-20.
  21. "CSIRAC: Australia's first computer". Australia: Commonwealth Scientific and Industrial Research Organisation (CSIRO). Retrieved 2007-12-21.
  22. Fildes, Jonathan (2008-06-17). "'Oldest' computer music unveiled". BBC News Online. Retrieved 2008-06-18.another oldest known recording of computer realized music played by the Ferranti Mark 1, captured by BBC in Autumn, 1951; the songs Baa Baa Black Sheep and In the Mood.
  23. Hiller, Lejaren (Winter 1981). "Composing with Computer: A Progress Report". Computer Music Journal. 5 (4).
    also available in Curtis Roads (ed.). The Music Machine: Selected Readings from Computer Music Journal. MIT Press (1989/1992). pp. 75. ISBN 978-0-262-68078-3.
  24. Hinton, Graham (2001). "Synthi 100 (1971, formerly Digitana, aka the Delaware)". Electronic Music Studios (Cornwall).
  25. Hinton, Graham (2001). "Synthi Sequencer 256 (1971, formerly Synthi Moog Sequencer)". Electronic Music Studios (Cornwall).
  26. J.Michmerhuizen (Boston School of Electronic Music); Thomas E. Oberheim (Oberheim Electronics) (June 1974). DS-2 Digital Sequencer Instruction and Service Manual (PDF). Cite uses deprecated parameter |coauthor= (help)
  27. "Model 800 Sequencer".
  28. Russ, Martin (2008). Sound Synthesis and Sampling. Focal Press. p. 346. ISBN 0240521056. Retrieved 21 June 2011.
  29. Gordon Reid. "The History Of Roland Part 1: 1930-1978". Sound On Sound (Nov 2004). Retrieved 2011-06-19.
  30. "Synclavier Early History". Synclavier European Services.
  31. Joel Chadabe (May 1, 2001). "The Electronic Century Part IV: The Seeds of the Future". Electronic Musician. In September 1977, I bought the first Synclavier, although mine came without the special keyboard and control panel ... (see Fig. 1 on the page).

Further reading

List of papers sharing a similar perspective with this Wikipedia article:

External links

Look up sequencer in Wiktionary, the free dictionary.
Wikimedia Commons has media related to Music sequencers.
This article is issued from Wikipedia - version of the 9/22/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.