Typical analog sequencer (
Korg SQ-10)
Buchla 146 Sequential Voltage Source module (16step × 3) with
114 keyboard on
Buchla 100 at
NYU (
c. 1964).
Moog 960 Sequential Controller with
962 Sequential Switch modules (1968–) on
Moog Modular 55 (1972–1981)
An analog sequencer is a music sequencer constructed from analog (analogue) electronics, invented in the first half of the 20th century.
Raymond Scott designed and constructed some of the first electro-mechanical music sequencers in the 1940s. The first electronic sequencer was invented by Raymond Scott, using thyratrons and relays. [1] Incidentally in 1951, computer music was started from the music sequencing, and later its applicable fields were expanded into the music composition and sound generation. However, the RCA Mark II Sound Synthesizer in 1957 was still indirectly controlled via punch-tape system similar to piano rolls, a kind of mechanical sequencer. Also, in earlier electronic music, artists used sound-on-film technology to generate sound waves as well as control sequences of notes.
At its most basic, an analog sequencer consists of a bank of potentiometers and a "clock" (pulse generator) connected to a sequencer, which steps through these potentiometers one at a time and then cycles back to the beginning. The output from the above is fed (as a control voltage and gate pulse) to a synthesizer. By "tuning" the potentiometers, a short repetitive rhythmic motif or riff can be set up.
The most commonly used analog sequencer was the Moog 960, which was a module of the Moog modular synthesizer. It consisted of three parallel banks of eight potentiometers: the three banks could either steer three different Voltage-controlled oscillators (VCOs) to allow three-note chords in the sequence, or (for example) one row could steer pitch while the second row is patched through to the filter cutoff or VCA volume, and a third steers filter cutoff for a white noise generator (thus creating an extremely primitive electronic drum track).
Under each of the eight steps, a switch offered three options: play this step, skip this step, or loop back to the beginning. To avoid the monotony of endlessly repeated sequences, pioneering electronic musicians like Chris Franke of Tangerine Dream and Michael Hoenig would manipulate these switches in real time during performance, adding and dropping notes and beats from a sequence. Also, the "pitch" row can be patched to two or more oscillators tuned to intervals, and the oscillators mixed in and out one at a time.
Good examples of all these techniques can be heard on the Phaedra, Rubycon, Ricochet, and Encore albums of Tangerine Dream, as well as on Departure from the Northern Wasteland by Michael Hoenig.
By synchronizing two sequencers, and manipulating them individually, swirling polyrhythmic phasing patterns (as introduced in minimalist music by Steve Reich) can be set up. The title track of the Michael Hoenig album (mentioned above) is an excellent example.
An additional module (Moog 962) allowed "daisy-chaining" the three rows to form one longer 24-step sequence. In addition, a switch on the 960 itself let the third (bottom) row be used for note lengths.
The output voltage of the sequencer can be added to the output voltage of a keyboard controller, and the latter used to transpose the sequence on the fly. Klaus Schulze was particularly fond of this technique, which lays the musical foundation for tracks like "Bayreuth Return" from Timewind, "Floating" from Moondawn, and any rhythmic piece from Klaus Schulze's "analog" years. Vangelis and Jean-Michel Jarre likewise availed themselves of this technique.
Apart from a temperature-controlled environment after warmup, pitch stability could be problematic. On the famous opening of Phaedra, the sequencer had drifted out of tune, and one can clearly hear Chris Franke retuning the sequence by ear in real time.
In addition to the 1027 module, which is a conventional 3x10 step sequencer, the ARP 2500 was often equipped with the 1050 Mix-Sequencer module. Unlike contemporary sequencers that only generated voltages, the 1050 could also sequence audio signals. This allowed each step of the sequence to come from a completely different sound source. The 8 positions could run in sequence or be split into two independent four-step sequencers. It's easily identified by its vertical column of 8 square white buttons that light up to indicate the active step(s).
Analog sequencers, have in some respects, been replaced by digital devices and software implementations. However, there is a continued interest by modular analog synthesists, who appreciate the real time control offered by the analog sequencer as evidenced by the 'Oberkorn' machine by Analog Solutions, amongst others.
- Various analog sequencers
An electronic musical instrument or electrophone is a musical instrument that produces sound using electronic circuitry. Such an instrument sounds by outputting an electrical, electronic or digital audio signal that ultimately is plugged into a power amplifier which drives a loudspeaker, creating the sound heard by the performer and listener.
An analogsynthesizer is a synthesizer that uses analog circuits and analog signals to generate sound electronically.
Modular synthesizers are synthesizers composed of separate modules for different functions. The modules can be connected together by the user to create a patch. The outputs from the modules may include audio signals, analog control voltages, or digital signals for logic or timing conditions. Typical modules are voltage-controlled oscillators, voltage-controlled filters, voltage-controlled amplifiers and envelope generators.
CV/gate is an analog method of controlling synthesizers, drum machines, and similar equipment with external sequencers. The control voltage typically controls pitch and the gate signal controls note on-off.
ARP Instruments, Inc. was a Lexington, Massachusetts manufacturer of electronic musical instruments, founded by Alan Robert Pearlman in 1969. It created a popular and commercially successful range of synthesizers throughout the 1970s before declaring bankruptcy in 1981. The company earned a reputation for producing excellent sounding, innovative instruments and was granted several patents for the technology it developed.
The VCS 3 is a portable analog synthesizer with a flexible modular voice architecture introduced by Electronic Music Studios (London) Limited (EMS) in 1969.
A voltage-controlled filter (VCF) is an electronic filter whose operating characteristics can be set by an input control voltage. Voltage controlled filters are widely used in synthesizers.
Buchla Electronic Musical Instruments (BEMI) was a manufacturer of synthesizers and unique MIDI controllers. The origins of the company could be found in Buchla & Associates, created in 1963 by synthesizer pioneer Don Buchla of Berkeley, California. In 2012 the original company led by Don Buchla was acquired by a group of Australian investors trading as Audio Supermarket Pty. Ltd. The company was renamed Buchla Electronic Musical Instruments as part of the acquisition. In 2018 the assets of BEMI were acquired by a new entity, Buchla U.S.A., and the company continues under new ownership.
The Moog synthesizer is a modular synthesizer invented by the American engineer Robert Moog in 1964. Moog's company, R. A. Moog Co., produced numerous models from 1965 to 1981, and again from 2014. It was the first commercial synthesizer and established the analog synthesizer concept.
The Moog model 2090 Micromoog is a monophonic analog synthesizer produced by Moog Music from 1975 to 1979.
Donald Buchla was an American pioneer in the field of sound synthesis. Buchla popularized the "West Coast" style of synthesis. He was co-inventor of the voltage controlled modular synthesizer along with Robert Moog, the two working independently in the early 1960s.
The ARP 2500 is a monophonic analog modular synthesizer. It was the first product of ARP Instruments, Inc., built from 1970 to 1981.
Electronic Music Laboratories, commonly abbreviated to EML, was a synthesizer company founded in 1968 in Vernon, Connecticut, by four engineers. It manufactured and designed a variety of synthesizers sharing the same basic design but configured in different ways.
The Serge synthesizer is an analogue modular synthesizer system originally developed by Serge Tcherepnin, Rich Gold and Randy Cohen at CalArts in late 1972. The first 20 Serge systems were built in 1973 in Tcherepnin's home. Tcherepnin was a professor at CalArts at the time, and desired to create something like the exclusively expensive Buchla modular synthesizers "for the people that would be both inexpensive and powerful." After building prototypes, Tcherepnin went on to develop kits for students to affordably build their own modular synthesizer, production taking place unofficially on a second floor CalArts balcony. This led to Tcherepnin leaving CalArts in order to produce synths commercially, starting in 1974.
A synthesizer is an electronic musical instrument that generates audio signals. Synthesizers typically create sounds by generating waveforms through methods including subtractive synthesis, additive synthesis and frequency modulation synthesis. These sounds may be altered by components such as filters, which cut or boost frequencies; envelopes, which control articulation, or how notes begin and end; and low-frequency oscillators, which modulate parameters such as pitch, volume, or filter characteristics affecting timbre. Synthesizers are typically played with keyboards or controlled by sequencers, software or other instruments and may be synchronized to other equipment via MIDI.
The Steiner-Parker Synthacon is a monophonic analog synthesizer that was built between 1975 and 1979 by Steiner-Parker, a Salt Lake City-based synthesizer manufacturer. It was introduced as a competitor to other analog synthesizers, like the Minimoog and ARP Odyssey.
The Mother-32 is a semi-modular analog synthesizer. Introduced in 2015, it was the first tabletop unit produced by Moog Music. It has a single voltage controlled audio oscillator, a voltage controlled low frequency oscillator, a voltage controlled filter switchable between high and low pass, an AR envelope generator with switchable sustain, a voltage controlled amplifier, and a white noise generator. It also features a 32–step monophonic sequencer, a 13-note keypad, and a 32-point patch bay including assignable outputs. The Mother-32 is manufactured in Asheville, North Carolina.
The Mother-32 is an analog semi-modular desktop synthesizer released by Moog Music Inc. in 2015.
The Volca Modular is an analogue synthesizer manufactured by the Japanese music technology company Korg. It is part of their popular Volca series of affordable electronic synthesizers and drum machines. Like other Volcas, it sports a 16-step sequencer and can be powered by batteries.
One of the first commercially available analog sequencers (bottom, 3×8-step and 3×16-step) on Buchla 100 (1964/1966) [2]
Earlier Moog sequencer (left, added after 1968) on the 1st commercially sold Moog Modular prototype (c.1964)
EML Sequencer 400 (top ×2, 6×16 step) on EML ElectroComp modular synthesizer (1970)
A Moog 960 clone,
Roland System 100M Model 182 Sequencer
Doepfer MAQ16-3 MIDI Analog Sequencer
