Metal disc with punched holes (late 18th century) — utilized on several music boxes such as Polyphon, Regina, Symphonion, Ariston, Graphonola (early version), etc.
Punch tape system for earliest studio synthesizers
RCA Mark II Sound Synthesizer by Herbert Belar and Harry Olson at RCA, a room-filling device built in 1957 for half a million dollars. Included a 4-polyphony synth with 12 oscillators, a sequencer fed with wide paper tape, with output recorded by a disc cutting lathe.
Variophone (1930) by Evgeny Sholpo—on earliest 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) by Osmond Kendal—rhythmical sequences were controlled via marking cue on film, while timbre of note or envelope-shape of sound were defined via hand drawn shapes on a surface of a CRT input device, drawn with a grease pencil.[3]
ANS synthesizer (1938-1958) by Evgeny Murzin—an earliest realtime additive synthesizer using 720 microtonal sine waves (1/6 semitones × 10 octaves) generated by five glass discs. Composers could control the time evolution of amplitudes of each microtone via scratches on a glass plate user interface covered with black mastic.
Oramics (1957) by Daphne Oram—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).[4] Polyphonic sounds were obtained using multitrack recording technique.
Electro-mechanical sequencers
Wall of Sound (mid-1940s–1950s) by Raymond Scott—early electro-mechanical sequencer developed by Raymond Scott to produce rhythmic patterns, consistent with stepping relays, solenoids, and tone generators[5]
Circle Machine (1959) by Raymond Scott—electro-optical rotary sequencer developed by Raymond Scott to generate arbitrary waveforms, consistent with dimmer bulbs arranged in a ring, and a rotating arm with photocell scanning over the ring[6]
Yamaha CS30 (1977)—monophonic synthesizer keyboard with built-in 8-step analog sequencer
Analog-style step sequencers
Analog-style MIDI step sequencers
Since the analog synthesizer revivals in the 1990s, newly designed MIDI sequencers with a series of knobs or sliders similar to analog sequencer have appeared. These often equip CV/Gate and DIN sync interface along with MIDI, and even patch memory for multiple sequence patterns and possibly song sequences. These analog-digital hybrid machines are often called "Analogue-style MIDI step sequencer" or "MIDI analogue sequencer", etc.
Doepfer MAQ 16/3—MIDI analog sequencer, designed in cooperation with Kraftwerk
Doepfer Regelwerk—MIDI analog sequencer with MIDI controller
Typical step sequencers are integrated on drum machines, bass machines, groove machines, music production machines, and these software versions. Often, these also support the semi-realtime recording mode, too.
MFB Step 64—Standalone step sequencer dedicated for drum patterns (16 steps/4 tracks or 64 steps/1 track, 118 programs×4 banks, 16 song sequences, each with up to 128 sequences)[16]
Embedded self-contained step sequencers
Several tiny keyboards provide a step sequencer combined with an independent timing mode for recording and performance:
CasioVL-Tone VL-1 (1979), Casiotone MT-70 (c.1984), Sampletone SK-1 (1986), etc.—Timings of musical notes stored on the step sequencer, can be designated by the two trigger buttons labeled "One Key Play", around the right hand position
Embedded CV/Gate step sequencers
Several machines have white and black chromatic keypads, to enter the musical phrases.
Recently emerging button-grid-style interfaces/instruments are naturally support step sequence. On these machines, one axis on grid means musical scale or sample to play, and another axis means timing of notes.
Synthstrom Deluge - Piano-roll-style sequencing on 128 pads (16×8)
In addition, newly designed hardware MIDI sequencers equipping a series of knobs/sliders similar to analog sequencers, are appeared. For details, see #Analog-style MIDI step sequencers.
Digital sequencers
CV/Gate
Also often support Gate clock and DIN sync interfaces.
NED Synclavier series—CV/Gate interface and MIDI retrofit kit were available on Synclavier II. Also MIDI became standard feature on Synclavier PSMT[18][19]
Fairlight CMI series—CV/Gate interface was optionally available on Series II, and MIDI was supported on Series IIx and later models
^"Das Siemens-Studio für elektronische Musik von Alexander Schaaf und Helmut Klein" (in German). Deutsches Museum. Archived from the original on 2013-09-30.
^Holmes, Thom (22 May 2012). "Early Synthesizers and Experimenters". Electronic and Experimental Music: Technology, Music, and Culture (4th ed.). Routledge (published 2012). pp. 190–192. ISBN 978-1-136-46895-7. (See also excerpt of pp. 157–160 from Holmes 2008)
^"The Composer-Tron (1953)". 120 Years of Electronic Music (120years.net). Archived from the original on 2012-04-02.
^"Daphne Oram and 'Oramics' (1959)". 120 Years of Electronic Music (120years.net). Archived from the original on 2011-11-19.
^"Wall of Sound (sequencer)". RaymondScott.com. Archived from the original on 2011-11-13.
^"Circle Machine". RaymondScott.com. Archived from the original on 2011-09-27.—includes 2 sound files: Raymond Scott's demonstration, and commercial soundtrack for new batteries of Ford Motors.
^US patent 3,207,835, Howard E. Holman and Joseph H. Hearne (Wurlitzer Company), "Rhythm Device", issued 1965-09-21
^Holmes, Thom (2008). Electronic and experimental music: technology, music, and culture (3rd ed.). Routledge. p. 222. 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."
^"Moog 961 Interface". MoogArchives.com.—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.—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.—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.
^MFB-URZWERG, MFB Musik Elektronik, archived from the original on 2011-12-02
^MFB-URZWERG Pro, MFB Musik Elektronik, archived from the original on 2012-06-18
^Roland EF-303 Groove Effects - Owner's manual (PDF), Roland Corporation, pp. 48, 53, 54, archived from the original (PDF) on 2013-05-31
^Sequencer MFB-STEP64, MFB Musik Elektronik, archived from the original on 2012-04-05
^"SM0600 Project - A Digital Sequencer - Rebuilding the Roland CSQ-700". Emulator Archive.
^Furia, Steve De; Joe Scacciaferro (1986). The MIDI implementation book. Third Earth Pub. p. 25. ISBN 978-0-88188-558-3.—MIDI Implementation Chart of Synclavier MIDI Option v0.9 in 1985.
^Williams, Tonny (January 24, 1984), Rhodes Keyboards Instruments Chroma Computer Interface Model 1611 Rev 5—Sequencer Manual (PDF), CBS Inc.
^"External Key Code Interface Circuit" (PDF), Yamaha CS70M Servicing Manual, Yamaha Corporation, October 1981, p. 24, archived from the original (PDF) on 2016-04-21, retrieved 2016-09-18