|Hornbostel–Sachs classification||531.1  |
|Developed||1920; patented in 1928|
The theremin ( /ˈθɛrəmɪn/ ; originally known as the ætherphone/etherphone, thereminophone  or termenvox/thereminvox) is an electronic musical instrument controlled without physical contact by the performer (who is known as a thereminist). It is named after its inventor, Leon Theremin, who patented the device in 1928.
The instrument's controlling section usually consists of two metal antennas which function not as radio antennas but rather as position sensors. Each antennae forms one half of a capacitor with each of the thereminist's hands as the other half of the capacitor. These antennas capacitively sense the relative position of the hands and control oscillators for frequency with one hand, and amplitude (volume) with the other. The electric signals from the theremin are amplified and sent to a loudspeaker.
The sound of the instrument is often associated with eerie situations. The theremin has been used in movie soundtracks such as Miklós Rózsa's Spellbound and The Lost Weekend , Bernard Herrmann's The Day the Earth Stood Still , and Justin Hurwitz's First Man as well as in theme songs for television shows such as the ITV drama Midsomer Murders and the Disney+ series Loki, the latter composed by Natalie Holt. The theremin is also used in concert music (especially avant-garde and 20th- and 21st-century new music) and in popular music genres such as rock.
The theremin was the product of Soviet government-sponsored research into proximity sensors. The instrument was invented in October 1919 by the Russian physicist Lev Sergeyevich Termen, known in the West as Leon Theremin.   After a lengthy tour of Europe, during which time he demonstrated his invention to packed houses, Theremin moved to the United States, where he patented his invention in 1928.  Subsequently, Theremin granted commercial production rights to RCA.
Although the RCA Thereminvox (released immediately following the Stock Market Crash of 1929) was not a commercial success, it fascinated audiences in America and abroad. Clara Rockmore, a well-known thereminist, toured to wide acclaim, performing a classical repertoire in concert halls around the United States, often sharing the bill with Paul Robeson.
During the 1930s, Lucie Bigelow Rosen was also taken with the theremin and together with her husband Walter Bigelow Rosen provided both financial and artistic support to the development and popularisation of the instrument.  
In 1938, Theremin left the United States, though the circumstances related to his departure are in dispute. Many accounts claim he was taken from his New York City apartment by NKVD agents (preceding the KGB),  taken back to the Soviet Union and made to work in a sharashka laboratory prison camp at Magadan, Siberia. He reappeared 30 years later. In his 2000 biography of the inventor, Theremin: Ether Music and Espionage, Albert Glinsky suggested he had fled to escape crushing personal debts, and was then caught up in Stalin's political purges. In any case, Theremin did not return to the United States until 1991. 
After a flurry of interest in America following the end of the Second World War, the theremin soon fell into disuse with serious musicians, mainly because newer electronic instruments were introduced that were easier to play. However, a niche interest in the theremin persisted, mostly among electronics enthusiasts and kit-building hobbyists. One of these electronics enthusiasts, Robert Moog, began building theremins in the 1950s, while he was a high-school student. Moog subsequently published a number of articles about building theremins, and sold theremin kits that were intended to be assembled by the customer. Moog credited what he learned from the experience as leading directly to his groundbreaking synthesizer, the Moog. (Around 1955, a colleague of Moog's, electronic music pioneer Raymond Scott, purchased one of Moog's theremin subassemblies to incorporate into a new invention, the Clavivox, which was intended to be an easy-to-use keyboard theremin.) 
Since the release of the film Theremin: An Electronic Odyssey in 1993, the instrument has enjoyed a resurgence in interest and has become more widely used by contemporary musicians. Even though many theremin sounds can be approximated on many modern synthesizers, some musicians continue to appreciate the expressiveness, novelty, and uniqueness of using an actual theremin. The film itself has received positive reviews. 
Both theremin instruments and kits are available. The Open Theremin, an open hardware and open software project, was developed by Swiss microengineer Urz Gaudenz, using the original heterodyne oscillator architecture for a good playing experience,  combined with Arduino. Using a few extra components, a MIDI interface can be added to the Open Theremin, enabling a player to use their Theremin to control different instrument sounds. 
Recently Three radio theremin by Tomoya Yamamoto is very popular and can find many performance uploads in youtube using this method. This set up need only three usual AM radios and can try Theremin performance at ease. 
The theremin is distinguished among musical instruments in that it is played without physical contact. The thereminist stands in front of the instrument and moves their hands in the proximity of two metal antennas. The distance from one antenna determines frequency (pitch), and the distance from the other controls amplitude (volume). Higher notes are played by moving the hand closer to the pitch antenna. Louder notes are played by moving the hand away from the volume antenna.
Most frequently, the right hand controls the pitch and the left controls the volume, although some performers reverse this arrangement. Some low-cost theremins use a conventional, knob operated volume control and have only the pitch antenna. While commonly called antennas, they are not used as radio antennae for receiving or broadcasting radio waves, but rather act as plates of capacitors.
The theremin uses the heterodyne principle to generate an audio signal. The instrument's pitch circuitry includes two radio frequency oscillators set below 500 kHz to minimize radio interference. One oscillator operates at a fixed frequency. The frequency of the other oscillator is almost identical, and is controlled by the performer's distance from the pitch control antenna.
The performer's hand has significant body capacitance, and thus can be treated as the grounded plate of a variable capacitor in an L-C (inductance-capacitance) circuit, which is part of the oscillator and determines its frequency. In the simplest designs, the antenna is directly coupled to the tuned circuit of the oscillator and the 'pitch field', that is the change of note with distance, is highly nonlinear, as the capacitance change with distance is far greater near the antenna. In such systems, when the antenna is removed, the oscillator moves up in frequency.
To partly linearise the pitch field, the antenna may be wired in series with an inductor to form a series tuned circuit, resonating with the parallel combination of the antenna's intrinsic capacitance and the capacitance of the player's hand in proximity to the antenna. This series tuned circuit is then connected in parallel with the parallel tuned circuit of the variable pitch oscillator. With the antenna circuit disconnected, the oscillator is tuned to a frequency slightly higher than the stand alone resonant frequency of the antenna circuit. At that frequency, the antenna and its linearisation coil present an inductive impedance; and when connected, behaves as an inductor in parallel with the oscillator. Thus, connecting the antenna and linearising coil raises the oscillation frequency. Close to the resonant frequency of the antenna circuit, the effective inductance is small, and the effect on the oscillator is greatest; farther from it, the effective inductance is larger, and fractional change on the oscillator is reduced.
When the hand is distant from the antenna, the resonant frequency of the antenna series circuit is at its highest; i.e., it is closest to the free running frequency of the oscillator, and small changes in antenna capacitance have greatest effect. Under this condition, the effective inductance in the tank circuit is at its minimum and the oscillation frequency is at its maximum. The steepening rate of change of shunt impedance with hand position compensates for the reduced influence of the hand being further away. With careful tuning, a near linear region of pitch field can be created over the central 2 or 3 octaves of operation. Using optimized pitch field linearisation, circuits can be made where a change in capacitance between the performer and the instrument in the order of 0.01 picofarads produces a full octave of frequency shift. 
The mixer produces the audio-range difference between the frequencies of the two oscillators at each moment, which is the tone that is then wave shaped and amplified and sent to a loudspeaker.
To control volume, the performer's other hand acts as the grounded plate of another variable capacitor. As in the tone circuit, the distance between the performer's hand and the volume control antenna determines the capacitance and hence natural resonant frequency of an LC circuit inductively coupled to another fixed LC oscillator circuit operating at a slightly higher resonant frequency. When a hand approaches the antenna, the natural frequency of that circuit is lowered by the extra capacitance, which detunes the oscillator and lowers its resonant plate current.
In the earliest theremins, the radio frequency plate current of the oscillator is picked up by another winding and used to power the filament of another diode-connected triode, which thus acts as a variable conductance element changing the output amplitude.  The harmonic timbre of the output, not being a pure tone, was an important feature of the theremin.  Theremin's original design included audio frequency series/parallel LC formant filters as well as a 3-winding variable-saturation transformer to control or induce harmonics in the audio output. 
Modern circuit designs often simplify this circuit and avoid the complexity of two heterodyne oscillators by having a single pitch oscillator, akin to the original theremin's volume circuit. This approach is usually less stable and cannot generate the low frequencies that a heterodyne oscillator can. Better designs (e.g., Moog, Theremax) may use two pairs of heterodyne oscillators, for both pitch and volume. 
Important in theremin articulation is the use of the volume control antenna. Unlike touched instruments, where simply halting play or damping a resonator in the traditional sense silences the instrument, the thereminist must "play the rests, as well as the notes", as Clara Rockmore observed.  If the pitch hand is moved between notes, without first lowering the volume hand, the result is a "swooping" sound akin to a swanee whistle or a glissando played on the violin. Small flutters of the pitch hand can be used to produce a vibrato effect. To produce distinct notes requires a pecking action with the volume hand to mute the volume while the pitch hand moves between positions.
Thereminists such as Carolina Eyck use a fixed arm position per octave, and use fixed positions of the fingers to create the notes within the octave, allowing very fast transitions between adjacent notes.  Although volume technique is less developed than pitch technique, some thereminists have worked to extend it, especially Pamelia Kurstin with her "walking bass" technique  and Rupert Chappelle.
Recent versions of the theremin have been functionally updated: the Moog Ethervox, while functionally still a theremin, can also be used as a MIDI controller, and as such allows the artist to control any MIDI-compatible synthesizer with it, using the theremin's continuous pitch to drive modern synths.  The Harrison Instruments Model 302  Theremin uses symmetrical horizontal plates instead of a vertical rod and horizontal loop to control pitch and volume, with the volume increasing as the hand approaches the plate. Music From The Ether  manufactures a modernized vacuum tube replica of the RCA AR-1264 and a transistorized theremin which the customer may customize with a desired wood species, as well as many available tolex colors with matching knobs.
The critic Harold C. Schonberg described the sound of the theremin as "(a) cello lost in a dense fog, crying because it does not know how to get home." 
The first orchestral composition written for theremin was Andrei Pashchenko's Symphonic Mystery, which premiered in 1924.  However, most of the sheet music was lost after its second performance.  Other concert composers who have written for theremin include Bohuslav Martinů,  Percy Grainger,  Christian Wolff,  Joseph Schillinger,  Moritz Eggert,  Iraida Yusupova,  Jorge Antunes,  Vladimir Komarov,  Anis Fuleihan,   and Fazıl Say.  Another large-scale theremin concerto is Kalevi Aho's Concerto for Theremin and Chamber Orchestra "Eight Seasons" (2011), written for Carolina Eyck.
Edgard Varèse completed the composition ‘’Equatorial’’ for two Theremin Cellos and percussion in 1934. His work was a stated influence throughout the career of Frank Zappa,  who also composed for theremin. 
Maverick composer Percy Grainger chose to use ensembles of four or six theremins (in preference to a string quartet) for his two earliest experimental Free Music compositions (1935–37) because of the instrument's complete 'gliding' freedom of pitch.  
Musician Jean-Michel Jarre used the instrument in his concerts Oxygen In Moscow and Space of Freedom  in Gdańsk, providing also a short history of Léon Theremin's life.
The five-piece Spaghetti Western Orchestra use a Theremin as a replacement for Edda Dell'Orso's vocals in their interpretation of Ennio Morricone's "Once Upon a Time in the West". 
Other notable contemporary Theremin players include Pamelia Kurstin,  Peter Theremin, Natasha Theremin, Katica Illényi.  and Lydia Kavina,  Dutch classical musician Thorwald Jørgensen has been described as "one of the most important exponents of classical music on the theremin". 
In 2019 a group of 289 theremin players (Matryomin ensemble) (including daughter, granddaughter and great-grandson Lev Theremin - Natasha Theremin, Masha Theremin and Peter Theremin) in Kobu, Japan, achieved a Guinness world record as the largest theremin ensemble. The name Matryomin is a portmanteau of the words matryoshka and theremin.[ citation needed ]. The theremin concerto "Dancefloor With Pulsing" by the French composer Regis Campo was written for Carolina Eyck and premiered with the Brussels Philharmonic in 2018. 
Theremins and theremin-like sounds started to be incorporated into popular music from the end of the 1940s (with a series of Samuel Hoffman/Harry Revel collaborations)  and has continued, with various degrees of popularity, to the present. 
Lothar and the Hand People were the first rock band known to perform live with a theremin in November 1965. In fact, Lothar was the name they gave to their Moog theremin. 
The Beach Boys' 1966 single "Good Vibrations"—though it does not technically contain a theremin—is the most frequently cited example of the instrument in pop music. The song actually features a similar-sounding instrument invented by Paul Tanner called an Electro-Theremin.  Upon release, the single prompted an unexpected revival in theremins and increased the awareness of analog synthesizers.  In response to requests by the band, Moog Music began producing their own brand of ribbon-controlled instruments which would mimic the sound of a theremin. 
Frank Zappa also included the theremin on the albums Freak Out! (1966) and We're Only in It for the Money (1967). 
Jimmy Page of Led Zeppelin used a variation of the theremin (pitch antenna only) during performances of "Whole Lotta Love" and "No Quarter" throughout the performance history of Led Zeppelin, an extended multi-instrumental solo featuring theremin and bowed guitar in 1977, as well as the soundtrack for Death Wish II , released in 1982. 
Brian Jones of the Rolling Stones also used the instrument on the group's 1967 albums Between the Buttons and Their Satanic Majesties Request . 
Tesla guitarist Frank Hannon used a theremin in the band's song "Edison's Medicine" from the 1991 album Psychotic Supper .  Hannon is also seen using the instrument in the song's music video at the 2:40 mark. 
The Lothars are a Boston-area band formed in early 1997 whose CDs have featured as many as four theremins played at once – a first for pop music.  
Although credited with a "Thereman" [ sic ] on the track "Mysterons" from the album Dummy, Portishead actually used a monophonic synthesizer to achieve theremin-like effects, as confirmed by Adrian Utley, who is credited as playing the instrument;  on the songs "Half Day Closing", "Humming", "The Rip", and "Machine Gun" he has actually used a custom made theremin. 
Page McConnell, keyboardist of the American rock band Phish, plays the theremin on rare occasions. His last notable performance was on 6 August 2017, the final evening of the band's 13-night residency at Madison Square Garden. 
When Simon and Garfunkel performed their song "The Boxer" during a concert at Madison Square Garden in December, 2003, they utilized a theremin. The original recording of the song had featured a steel guitar and a piccolo trumpet in unison in the solo interlude, but for this performance, thereminist Rob Schwimmer played the solo. 
Russian composer Dmitri Shostakovich was one of the first to incorporate parts for the theremin in orchestral pieces, including a use in his score for the film Odna (Russian : Одна — 1931, Leonid Trauberg and Grigori Kozintsev). While the theremin was not widely used in classical music performances, the instrument found great success in many motion pictures, notably, Spellbound , The Red House , The Lost Weekend (all three of which were written by Miklós Rózsa, the composer who pioneered the use of the instrument in Hollywood scores), The Spiral Staircase , Rocketship X-M , The Day the Earth Stood Still , The Thing from Another World , Castle In the Air , and The Ten Commandments . The theremin is played and identified as such in the Jerry Lewis movie The Delicate Delinquent . The theremin is prominent in the score for the 1956 short film A Short Vision ,  which was aired on The Ed Sullivan Show the same year that it was used by the Hungarian composer Mátyás Seiber. More recent appearances in film scores include Monster House , Ed Wood , The Machinist  and The Electrical Life of Louis Wain  (2021), (last three featuring Lydia Kavina), as well as First Man (2018).
A theremin was not used for the soundtrack of Forbidden Planet , for which Bebe and Louis Barron built disposable oscillator circuits and a ring modulator to create the electronic tonalities used in the film.  
Los Angeles-based thereminist Charles Richard Lester is featured on the soundtrack of Monster House  and has performed the US premiere of Gavriil Popov's 1932 score for Komsomol – Patron of Electrification with the Los Angeles Philharmonic and Esa-Pekka Salonen in 2007. 
In Lenny Abrahamson's 2014 film, Frank , Clara, the character played by Maggie Gyllenhaal, plays the theremin in a band named Soronprfbs. 
Charlie Rosen, orchestrator of the Broadway musical Be More Chill , credits the show as being the first on Broadway to have a theremin in its band. 
The First Theremin Concert for Extraterrestrials was the world's first musical METI broadcast dispatched from the Evpatoria deep-space communications complex in Crimea,  and was sent seven years before NASA's Across the Universe message. Seven different melodies were transmitted from audio-cassette recordings of the theremin being played by Lydia Kavina, Yana Aksenova, and Anton Kerchenko, all from the Moscow Theremin Center. These seven melodies were:
They were played in succession six times over the span of three days from August–September 2001 during the transmission of Teen Age Message, an interstellar radio message. 
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.
Lev Sergeyevich Termen, better known as Leon Theremin, was a Russian inventor, most famous for his invention of the theremin, one of the first electronic musical instruments and the first to be mass-produced. He also worked on early television research. His secret listening device, "The Thing", hung for seven years in plain view in the United States Ambassador's Moscow office and enabled Soviet agents to eavesdrop on secret conversations.
Lydia Evgenevna Kavina is a Russian-British theremin player, based in Oxfordshire, UK.
Robert Arthur Moog was an American engineer and electronic music pioneer. He was the founder of the synthesizer manufacturer Moog Music and the inventor of the first commercial synthesizer, the Moog synthesizer, which debuted in 1964. In 1970, Moog released a more portable model, the Minimoog, described as the most famous and influential synthesizer in history. Among Moog's honors are a Technical Grammy Award, received in 2002, and an induction into the National Inventors Hall of Fame.
A heterodyne is a signal frequency that is created by combining or mixing two other frequencies using a signal processing technique called heterodyning, which was invented by Canadian inventor-engineer Reginald Fessenden. Heterodyning is used to shift signals from one frequency range into another, and is also involved in the processes of modulation and demodulation. The two input frequencies are combined in a nonlinear signal-processing device such as a vacuum tube, transistor, or diode, usually called a mixer.
Concerto per Theremin. Live in Italy is Lydia Kavina's second album. It was recorded in Italy in 1998 and released on CD by Teleura in 2000.
An analogsynthesizer is a synthesizer that uses analog circuits and analog signals to generate sound electronically.
The Electro-Theremin is an electronic musical instrument developed by trombonist Paul Tanner and amateur inventor Bob Whitsell in the late 1950s to produce a sound to mimic that of the theremin. The instrument features a tone and portamento similar to that of the theremin, but with a different control mechanism. It consisted of a sine wave generator with a knob that controlled the pitch, placed inside a wooden box. The pitch knob was attached to a slider on the outside of the box with some string. The player would move the slider, thus turning the knob to the desired frequency, with the help of markings drawn on the box. This contrasts with the theremin, which a performer plays without touching as two antennae sense the position and movement of the performer's hands.
A regenerative circuit is an amplifier circuit that employs positive feedback. Some of the output of the amplifying device is applied back to its input to add to the input signal, increasing the amplification. One example is the Schmitt trigger, but the most common use of the term is in RF amplifiers, and especially regenerative receivers, to greatly increase the gain of a single amplifier stage.
A variable frequency oscillator (VFO) in electronics is an oscillator whose frequency can be tuned over some range. It is a necessary component in any tunable radio transmitter and in receivers that works by the superheterodyne principle. The oscillator controls the frequency to which the apparatus is tuned.
Clara Reisenberg Rockmore was a Lithuanian classical violin prodigy and a virtuoso performer of the theremin, an electronic musical instrument. She was the sister of pianist Nadia Reisenberg.
In radio communications, a radio receiver, also known as a receiver, a wireless, or simply a radio, is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves and converts them to tiny alternating currents which are applied to the receiver, and the receiver extracts the desired information. The receiver uses electronic filters to separate the desired radio frequency signal from all the other signals picked up by the antenna, an electronic amplifier to increase the power of the signal for further processing, and finally recovers the desired information through demodulation.
A voltage-controlled oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input. The applied input voltage determines the instantaneous oscillation frequency. Consequently, a VCO can be used for frequency modulation (FM) or phase modulation (PM) by applying a modulating signal to the control input. A VCO is also an integral part of a phase-locked loop. VCOs are used in synthesizers to generate a waveform whose pitch can be adjusted by a voltage determined by a musical keyboard or other input.
The Moog synthesizer is a modular synthesizer developed by the American engineer Robert Moog. Moog debuted it in 1964, and 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 is credited with creating the analog synthesizer as it is known today.
Body capacitance is the physical property of the human body that it acts as a capacitor. Like any other electrically-conductive object, a human body can store electric charge if insulated. The actual amount of capacitance varies with the surroundings; it would be low when standing on top of a pole with nothing nearby, but high when leaning against an insulated, but grounded large metal surface, such as a household refrigerator, or a metal wall in a factory.
The Sphärophon or a Spherophone is an electrical musical instrument that was first made as the "Electrophon" around 1921 by Jörg Mager, later modified, renamed and exhibited in 1926.
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.
Georges Marcel Charles Jenny was a French musician, poet, and electronic instrument builder. His best-known invention was an electronic keyboard instrument called the Ondioline. It is considered a forerunner of the Synthesizer. The Ondioline is monophonic, yet it is capable of generating an array of sounds, and features a keyboard that produces a natural-sounding vibrato via side-to-side finger movements when keys are depressed.
The Moog Theremini is a monophonic digital synthesizer manufactured by Moog Music and is a re-working on one of the oldest electronic instruments in history, the Theremin, created by Léon Theremin in 1929 and made popular as a source of atmospheric sound tracks for science fiction films. Similar to the Theremin, the Theremini does not require physical contact to play it. Rather, the device gauges the proximity of the performer's hands to determine the parameters of a performed note. The left hand controls the amplitude (volume), and the right hand controls the frequency (pitch). Unlike the original Theremin, this unit is designed to be easier to play, as it also features pitch correction. The instrument was announced at the National Association of Music Merchants tradeshow in 2014.
Grégoire Blanc is a French musician who plays the theremin and the musical saw.
financially supported Léon Theremin's work