Music sequencer
The music sequencer (or simply sequencer) is a device or computer software to record, edit, play back the music, by handling note and performance information in several forms, typically : MIDI, CV/Gate, and possibly audio and automation data for Plug-ins and DAWs. [note 1][note 2]
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And also possibly includes :
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Note that computer software (or dedicated systems) mainly handle digital audio are traditionally called “Digital audio workstation” (DAW). Also note that normally, bare music sequencer doesn't directly handle audio; instead, musical instruments/effects devices controlled by sequencers, or audio engines/DAWs integrated with software sequencers, are used to handle audio.
Overview
Modern sequencers
With the advent of MIDI and particularly Atari ST in 1980s, programmers were able to write software that could record and play back the notes played by a musician. Unlike the early sequencers used to play mechanical sounding sequence with exactly equal length, the new ones recorded and played back expressive performances by real musicians. These were typically used to control external synthesizers, especially rackmounted sound modules as it was no longer necessary for each synthesizer to have its own keyboard.
As the technology matured, sequencers gained more features, and integrated the ability to record multitrack audio. Sequencers mainly used for audio are often called digital audio workstations (or DAWs).
Many modern sequencers can also control virtual instruments implemented as software plug-ins, allowing musicians to replace separate synthesizers with software equivalents.
In today, the term "sequencer" is often used for software, however, also hardwares sequencers are remained. 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.
See #Software sequencers / DAWs with sequencing features for detail listing.
Type of music sequencers
Music sequencers can be categorized with its sequence mode (or record mode):
Realtime mode: On the realtime sequencer, musical notes are recorded in realtime as on audio recorder, and played back with designated pitch, tempo and quantization. For realtime editing, "punch in/punch out" features are often supported, however, to edit details, another editing mode may be needed. Built-in sequencers on electronic keyboards often support realtime mode.
Step mode: On the step sequencer, musical notes are divided into steps, and each steps are recorded without exact timing. Instead, timing of each step are separately designated by order of entering steps (on bass machines), or selection of column buttons (on drum machines). Analog drum machines and bass machines often utilize this mode, along with semi-realtime mode.
Analog sequencers are sometimes confused with step sequencers, however, concepts of realtimeness and tempo are significantly different. Typical analog sequencers were designed for realtime composition and performance using multiple knobs/sliders, so, notes on sequence are always changeable without entering record mode. In addition, time between each notes (steps) are also adjustable independently.
- Software sequencers, in general, tend to support various sequence modes. Modern software sequencers with DAW features often support: piano rolls, strip charts, score edit, numerical edit, and also audio sequencing including rearrangement of sample loops, beat slicing, and pitch manipulation. Several sequencers are specialized to particular sequence mode: for example, loop-based music software specializing audio sequencer, software drum machines specializing step sequencer, etc.
History
Earlier sequencers
The earlier music sequencers had appeared in the form of various automatic musical instruments, including music boxes, mechanical organs, player pianos, etc. For example, authoring of piano roll resemble the definition of music sequencer. Several composers recorded their composition on piano rolls, then specialists edited rolls for the preparation of mass duplication, and finally consumers played back music on their player piano.
The origin of automatic musical instruments seems considerably old. As early as 9th century, Persian inventors Banū Mūsā brothers invented hydropowered organ using exchangeable cylinders with pins,[2] and also automatic flute player using steam power,[3][4] as described on their Book of Ingenious Devices. In 14th century, rotating cylinder with pins were used to play carillon in Flanders, and at least in 15th century, barrel organs were seen in the Netherlands.[5] In 19th century, as the result of the Industrial Revolution, various automatic musical instruments were invented, includes music box, barrel organ and barrel piano using barrel / cylinder / metal disc with pins, or mechanical organ, orchestrion and player piano using book music / music rolls (piano rolls) with punched holes, etc. These instruments widely spread as the popular entertainment devices, before the invention of phonograph and radio.
Also in 20th century, earliest programmable music synthesizers , RCA Mark II Sound Synthesizer in 1957, and Siemens Synthesizer in 1959, were controlled via punch tapes similar to piano rolls. [6][7]
On the other hand, Raymond Scott, an American composer of electronic music, invented various music sequencers during 1940s–1960s for his electric compositions. The Wall of Sound, once covered on the wall of his studio in 1940s, was a electro-mechanical sequencer to produce rhythmic patterns, consisted with stepping relays (used on dial pulse telephone exchange), solenoids, control switches, and tone circuits with 16 individual oscillators. [8] Later, Robert Moog explained it “the whole room would go 'clack - clack - clack', and the sounds would come out all over the place”.[9] 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.[10] And relatively well known Clavivox, developed since 1952, was a kind of keyboard synthesizer with sequencer. On its prototype, theremin manufactured by young Robert Moog was utilized to enable portamento over 3-octave range, and on later version, instead photographic film and photocell were utilized to control pitch by voltage. [9]
With the relation to the photographic films, the drawn sound technique that appeared in the late 1920s, may be also important 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.
One of the earliest commercially available analog sequencer (front) on
Buchla 100 (1964/1966)
[11][12]
Moog sequencer module (left, probably added after 1968) on
Moog Modular (1964)
Analog sequencers
Step sequencers
Eko ComputeRhythm (1972),
[13][14] one of the earliest programm-
able drum machine
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
On the other hand, software sequencers were continuously utilized since 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, first computer music Colonel Bogey was played on CSIRAC, Australia's first digital computer.[16][17] In 1956, Lejaren Hiller at University of Illinois at Urbana-Champaign wrote an earliest program for computer music composition on ILLIAC, and collaborated on the first piece, Illiac Suite for String Quartet, with Leonard Issaction.[18] In 1957, Max Mathews at Bell Labs wrote MUSIC, a first widely-used program for sound generation, and 17 second composition was performed by the IBM 704 computer. Since then, computer music were mainly researched on the expensive mainframe computers at the computer centers, until minicomputers and later microcomputers went into practice on this field in 1970s.
Digital sequencers
EMS Sequencer 256 (1971), branched product from Synthi 100
In 1971, Electronic Music Studios (EMS) released one of the first digital sequencer products as a module of Synthi 100, and separated products Synthi Sequencer series.[19][20] After then, Oberheim released DS-2 Digital Sequencer in 1974,[21], and Sequential Circuits released Model 800 in 1977 [22]
Also in 1977, Roland Corporation released their first microcomputer-based digital sequencer, MC-8 Microcomposer, also called computer music composer by Roland. [23] It equipped keypad to enter note in numeric code, 16KB RAM for maximum 5200 notes (large enough at that time), and polyphony function which allocates multiple pitch CV into single Gate. [24] The earliest known user was Yellow Magic Orchestra, an electronic music group in 1978, [25] they created new sounds not possible until then.[26]
Software sequencers
In 1975, New England Digital (NED) released ABLE computer (microcomputer)[27] as a dedicated data processing unit for Dartmouth Digital Synthesizer (1973), and based on it, later Synclavier series were developed. Synclavier I, released in September 1977,[28] was one of the earlier digital music workstation product with multitrack sequencer. Synclavier series evolved throughout late 1970s–mid 1980s, and they integrated digital-audio and music-sequencer, on the Direct-to-Disk option in 1984, and later Tapeless Studio system.
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.
Short timeline of rhythm sequencers
Hardware sequencers
Many synthesizers, and by definition all workstations and drum machines, contain their own sequencers.
Following are specifically designed to function primarily as sequencers:
Rotating object with pins
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Punched paper
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Sound-on-film
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- Variophone (1930) — on earlier version, hand drawn waves on film or disc were used to synthesize sound, and later versions were promised to experiment on musical intonations and temporal characteristics of live music performance, however not finished. Variophone is often referred as a forerunner of drawn sound system including ANS synthesizer and Oramics.
- Composer-Tron (1953) — rhythmical sequences were controlled via marking cue on film, while timbre of note or envelope shape of sound were defined via shapes hand drawn with a grease pencil on a surface of CRT input device.[29]
- ANS synthesizer (1957) — An earliest realtime additive synthesizer using 720 microtonal sine waves (1/6 semitones × 10 octaves) generated by five glas discs. Composers could control time evolution of amplitudes of each microtones via scratches on glass plate user interface covered with black mastic.
- Oramics (1957) — hand drawn contours on a set of ten sprocketed synchronized strips of 35 film were used to control various parameters of monophonic sound generator (frequency, timbre, amplitude and duration).[30] Polyphonic sounds were obtained using multitrack recording technique.
Electro-mechanical sequencers
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- Wall of Sound (mid 1940s–1950s) — earlier electro-mechanical sequencer developed by Raymond Scott to produce rhythmic patterns, consistead with stepping relays, solenoids, and tone generators.[8]
- Circle Machine (1959) — electro-optical rotary sequencer developed by Raymond Scott to generate arbitrary waveforms, consisted with dimmer bulbs arranged in a ring, and a rotating arm with photocell scanning over the ring.[10]
Analog sequencers
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- Analog sequencers with CV/Gate interface
- Sequencers on Buchla 100 (1964/1966–) — One of the earliest analog sequencer in the modular synthesizer era since 1960. Later, Robert Moog admired Buchla's unique works including it.[11][12]
- Moog 960 Sequential Controller[31] / 961 Interface [32] / 962 Sequential Switch[33] (c.1968)[34]
- modules for the Moog modular synthesizer system, a popular analog sequencer following earlier Buchla sequencer.
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- Doepfer Dark Time
- genoQs Octopus
- genoQs Nemo
- Korg SQ-10
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|
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- Analog-style MIDI step sequencers
- Since the analog synthesizer revivals in 1990s, newly designed MIDI sequencers were released. These equip multiple knobs or sliders similar to analog sequencer, CV/Gate and DIN sync interface, and even patch memory for sequence patterns. These analog-digital hybrid machines are often called Analog-style MIDI step sequencer or MIDI analog sequencer, etc.
- Doepfer MAQ 16/3 — MIDI analog sequencer, designed in cooperation with Kraftwerk
- Doepfer Regelwerk — MIDI analog sequencer with MIDI controller
- Frostwave Fat Controller
- Infection Music Phaedra
- Infection Music Zeit
- Latronic Notron
- Manikin Schrittmacher
- Sequentix P3
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- MIDI pattern sequencers
- Several machines have also song mode to play sequence patterns on patch memory in specified order, as on drum machine.
- Doepfer Schaltwerk —MIDI pattern sequencer
Step sequencers (supported on)
- Typical step sequencers are integrated on drum machines, bass machines, groove machines, music production machines, and these software versions. And also these often support (semi-)realtime mode.
- Several machines have white & black chromatic keypads, to enter musical scale of bass lines, etc.
- embedded CV/Gate step sequencers
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- embedded MIDI step sequencers
- Other groovebox-type machines (including several music production machines) also often support step sequence mode, of course. :
- Recently emerging button-grid-style interfaces/instruments are naturally support step sequence. On these machines, one axis on grid means musical scale, and another axis means timing of notes.
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- In addition, newly designed hardware MIDI sequencers equipping series of knobs/sliders similar to analog sequencers, are sometimes called "MIDI step sequencer", etc. For details, see #Analog-style MIDI step sequencers.
Digital sequencers
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- CV/Gate
- Also often support Gate clock and DIN sync interfaces.
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- Proprietary digital interface (pre MIDI)
- NED Synclavier series — CV/Gate interface and MIDI retrofit kit were available on Synclavier II. Also MIDI became standard feature on Synclavier PSMT. [36][37]
- Fairlight CMI series — CV/Gate interface was optionally available on Series II, and MIDI was supported on Series IIx and later models.
- Oberheim DSX (Oberheim Parallel Bus)
- PPG Wave family (PPG Bus)
- Roland JSQ-60 (Roland Digital Control Bus (DCB))
- Sequential Circuits PolySequencer 1005 (SCI Serial Bus)
- Also Yamaha used proprietary digital interface on their earlier digital products. For example, YIS PU-I-20/PU-I-10 ca. 1981, a home automation computer system before MSX, enabled integration of home electronics including player piano, Electone (electronic organ), and remote music keyboard.[38][39]
MIDI sequencers
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- Embedded MIDI sequencers
- Accompaniment machines
- See also #embedded MIDI step sequencers.
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- Standalone MIDI sequencers
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- Akai ASQ10
- Alesis MMT-8
- Korg SQ-8 — palmtop
- Korg SQD-1
- Korg SQD-8
- Kawai Q-80
- Roland MC-327
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- Roland MC series: MC-50/MC-50MkII/MC-80/MC-300/MC-500 Microcomposer
- MSQ-100 (1985)
- MSQ-700 (1984) — one of the earliest multitrack MIDI sequencer (8tr),[40] a buddy of TR-909
- Roland PMA-5 — palmtop with touch screen
- Roland SB-55 — SMF recorder
- Yamaha QX series: QX1/QX3/QX5/QX7/QX21
- Yamaha QY300 — with embedded sound module
- Yamaha QY700 — with embedded sound module
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- See also: #Analog-style MIDI step sequencers
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- MIDI phrase sequencers
Uncategorized sequencers
- (not yet)
Software sequencers / DAWs with sequencing features
Free/Open Source
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- DAW with MIDI sequencers
- MIDI sequencers
- Loop-based MIDI sequencers
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- Loop-based audio sequencers
- Integrated software studio environments
- Drum machines
- Scorewriters
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- Not categorized yet
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- DAWs/HD recorders
- Ardour - Linux, Mac OS X, FreeBSD (Note: No sequence feature found)
- Others
Commercial
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- DAWs with MIDI sequencers
- Loop-oriented DAWs with MIDI sequencers
- Tracker-oriented DAWs with MIDI sequencers
- MIDI sequencers
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- Integrated software studio environments
- Loop-based audio sequencers
- Live Touch XJ, from Ematrade - Android 3.0 Honeycomb tablet
- Loopseque from Casual Underground Lab - iPad/iPhone
- Realtime arrangers with MIDI sequencers
- Piano training software
- Scorewriters
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- Not categorized yet
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- Realtime orchestral accompaniments
- Sinfonia , from Realtime Music Solutions (Note: It seems not the sequencer)
- Hard Disk recorder solutions for MIDI sequencers
- WinAudio from Zadok Audio & Media Products
- Others
See also
Notes
- ^ On today, software music sequencers integrated with DAWs are often supporting digital audio. However, bare music sequencers normally not directly handle the digital audio (except for “audio sequencers” which often means DAW). Instead, the audio engine consisted with DAW and plug-in host handles digital audio, and collaborates with bare music sequencer for synchronization and automation. Thus, handling of digital audio is not the essential role of music sequencers, in general.
- ^ Similarly, today's software music sequencers often mainly support MIDI and plug-ins (running on plug-in host). However, these are not essential on generic definition of music sequencers. On the long history of electronic music, various type of music sequencers handled various forms of music information, as following:
- Analog sequencers handle analog control data (ex. CV/Gate)
- Several digital devices/music software handle proprietary digital format data on its sequencer. (ex. earlier Music workstations and sequencers developed before MIDI era, self-contained integrated environments, or relatively simple devices without MIDI/USB IF).
- Plug-in's numerous parameters and DAW's automation data are often handled without MIDI mapping; in the case, these data might be clearly non MIDI data.
Over the all, definition of music sequencer shouldn't be limited with specific data formats. Instead, more generic information including notes and performance information, various control parameters of instruments/effects/DAWs, and even audio data itself, should be taken into account.
- ^ 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.
References
- ^ "Cubase 6 screenshot licensed under CC-BY-SA-3.0". Steinberg Media Technologies GmbH. http://www.steinberg.net/en/landing_pages/c6_creative_commons.
- ^ Fowler, Charles B. (October 1967). "The Museum of Music: A History of Mechanical Instruments". Music Educators Journal (Music Educators Journal) 54 (2): 45–49. doi:10.2307/3391092. JSTOR 3391092.
- ^ Koetsier, Teun (2001). "On the prehistory of programmable machines: musical automata, looms, calculators". Mechanism and Machine Theory (Elsevier) 36 (5): 589–603. doi:10.1016/S0094-114X(01)00005-2.
- ^ Banu Musa (authors) (1979). Donald Routledge Hill (translator). ed. The book of ingenious devices (Kitāb al-ḥiyal). Springer. pp. 76–7. ISBN 9027708339.
- ^ Chisholm, Hugh, ed (1911). "Barrel-organ". Encyclopædia Britannica (11th ed.). Cambridge University Press.
- ^ "The RCA Synthesiser". 120 Years of Electronic Music. http://120years.net/machines/rca/. — (PDF version is available])
- ^ a b "Das Siemens-Studio für elektronische Musik von Alexander Schaaf und Helmut Klein" (in Deutsch). Deutsches Museum. http://www.deutsches-museum.de/sammlungen/ausgewaehlte-objekte/meisterwerke-vi/siemens-studio/.
- ^ a b "Wall of Sound (sequencer)". RaymondScott.com. http://raymondscott.com/1946.htm.
- ^ a b Robert Moog. "Memories of Raymond Scott". RaymondScott.com. http://raymondscott.com/moog.html.
- ^ a b "Circle Machine". RaymondScott.com. http://raymondscott.com/circle.html. — includes 2 sound files: Raymond Scott's demonstration, and commercial soundtrack for new batteries of Ford Motors.
- ^ a b Holmes, Thom (2008). Electronic and experimental music: technology, music, and culture. Taylor & Francis. p. 222. ISBN 9780415957816. "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.”"
- ^ a b Miller, David (May 9, 2001), personal communication with Thom Holmes
- ^ "EKO Computerhythm (1972)". Jarrography - The ultimate Jean Michel Jarre discography. http://www.jarrography.free.fr/details_equipement_audio.php?id_equip=117.
- ^ "EKO Computerhythm". SynthMaster.de. http://www.synthmaster.de/ekodrum.htm.
- ^ "Multivox International" (in Germany). SYNRISE. Archived from the original on 2003-04-20. http://web.archive.org/web/20030420170643/http://www.synrise.de/docs/types/f/firstman.htm.
- ^ "CSIRAC: Australia's first computer". http://www.csiro.au/science/ps4f.html. Retrieved 2007-12-21.
- ^ Fildes, Jonathan (2008-06-17). "'Oldest' computer music unveiled". BBC News Online. http://news.bbc.co.uk/1/hi/technology/7458479.stm. 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.
- ^ Hiller, Lejaren (Winter 1981). "Composing with Computer: A Progress Report". Computer Music Journal 5 (Winter 1981).
also available in Curtis Roads, ed. The Music Machine: Selected Readings from Computer Music Journal. MIT Press (1989/1992). pp. 75. ISBN 9780262680783.
- ^ Hinton, Graham (2001). "Synthi 100 (1971, formerly Digitana, aka the Delaware)". Electronic Music Studios (Cornwall). http://www.ems-synthi.demon.co.uk/emsprods.html#synthi100.
- ^ Hinton, Graham (2001). "Synthi Sequencer 256 (1971, formerly Synthi Moog Sequencer)". Electronic Music Studios (Cornwall). http://www.ems-synthi.demon.co.uk/emsprods.html#seq256.
- ^ J.Michmerhuizen (Boston School of Electronic Music); Thomas E. Oberheim (Oberheim Electronics) (June 1974). DS-2 Digital Sequencer Instruction and Service Manual. http://www.cem3374.com/docs/Manuals/Oberheim/DS2_O&SM.pdf.
- ^ "Model 800 Sequencer". SynthMuseum.com. http://www.synthmuseum.com/sequ/seqseq80001.html.
- ^ Russ, Martin (2008). Sound Synthesis and Sampling. Focal Press. p. 346. ISBN 0240521056. http://books.google.co.uk/books?id=_D2cTt5DPmEC&pg=PA346. Retrieved 21 June 2011.
- ^ Gordon Reid (Nov. 2004). "The History Of Roland Part 1: 1930-1978". Sound On Sound. http://www.soundonsound.com/sos/nov04/articles/roland.htm. Retrieved 2011-06-19.
- ^ Yellow Magic Orchestra — Yellow Magic Orchestra at Discogs
- ^ "Artists and producers strive for inroads overseas". Billboard 91 (20): 61. 26 May 1979. ISSN 0006-2510. http://books.google.co.uk/books?id=_iQEAAAAMBAJ&pg=PT61. Retrieved 2011-05-29.
- ^ "Synclavier Early History". Synclavier European Services. http://www.500sound.com/synclavierhistory.html.
- ^ Joel Chadabe (May 1, 2001). "The Electronic Century Part IV: The Seeds of the Future". Electronic Musician. http://emusician.com/tutorials/electronic_century4/. "In September 1977, I bought the first Synclavier, although mine came without the special keyboard and control panel ... (see Fig. 1 on the page)."
- ^ "The Composer-Tron (1953)". 120years.net. http://120years.net/machines/composertron/.
- ^ "Daphne Oram and 'Oramics' (1959)". 120 Years of Electronic Music. http://120years.net/machines/oramics/index.html.
- ^ "Moog 960 Sequential Controller". MoogArchives.com. http://moogarchives.com/m960.htm. — 3×8 step sequencer module
- ^ "Moog 961 Interface". MoogArchives.com. http://moogarchives.com/m961.htm. — interface module to convert several signal types including audio input, V-trigger (CV), and S-trigger (short-to-ground trigger for Envelope Controller)
- ^ "Moog 962 Sequential Switch". MoogArchives.com. http://moogarchives.com/m962.htm. — switching module for 960 to convert 3x8 step sequence into 1x24 step sequence, etc.
- ^ "Synthesizer 2C with optional 960 and 961 - 1968 Modular System "Synthesizer 2"". MoogArchives.com. http://moogarchives.com/mod6802.htm. — On the MoogArchives.com, the photograph with caption "Synthesizer 2C with optional 960 and 961" on this page seems to be the earliest record of Moog's sequencer module.
- ^ "SM0600 Project - A Digital Sequencer - Rebuilding the Roland CSQ-700". Emulator Archive. http://www.emulatorarchive.com/AM/AMProjects/CSQ600/csq600.html.
- ^ Brandon Amison (17 Jul. 1999). "Yaking Cat Music Studios QAQA answers - Subject:0033 Re:Clothing ETC.". Yaking Cat Music Studios (Synclavier Assistance). http://home.earthlink.net/~yaking/html/answers/0033.html.
- ^ Furia, Steve De (1986). The MIDI implementation book. Third Earth Pub. p. 25. ISBN 9780881885583. — MIDI Implementation Chart of Synclavier MIDI Option v0.9 in 1985.
- ^ "Survey report on trends in electronic documents" (in Japanese). Japan Electronics and Information Technology Industries Association (JEITA). Archived from the original on June 2003. http://n-bz.sakura.ne.jp/around-the-music/essays/dtm-1sub.htm.
- ^ "Cool machines - Yamaha YIS PU-I-20" (in Japanese). http://www.geocities.jp/ahirudanna/zatsubun06.html. — a home automation system in 1982. System integration diagram is shown at the bottom of page.
- ^ "AM MSQ700 Nexus - MIDI Sequencer". Emulator Archive. http://www.emulatorarchive.com/AM/AMProjects/MSQ700/msq700.html.
External links