Lev Sergeyevich Termen (28 August [O.S. 16 August] 1896 – 3 November 1993), 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 secretly eavesdrop on conversations.
Leon Theremin was born in Saint Petersburg, Russia, in 1896. His father was Sergei Emilievich Theremin, of French Huguenot descent. His mother was Yevgenia Antonova Orzhinskaya, who was of German ancestry. He had a sister named Helena.
In the seventh grade of his high school, in front of an audience of students and parents, he demonstrated various optical effects using electricity.
By the age of 17, he was in his last year of high school and had his own laboratory at home for experimenting with high-frequency circuits, optics and magnetic fields. His cousin, Kirill Fedorovich Nesturkh, then a young physicist, invited him to attend the defense of the dissertation of Abram Fedorovich Ioffe. Physics lecturer Vladimir Konstantinovich Lebedinskiy had explained to Theremin the dispute over Ioffe's work on the electron. On 9 May 1913, Theremin and his cousin attended Ioffe's dissertation defense. Ioffe's subject was on the elementary photoelectric effect, the magnetic field of cathode rays and related investigations. In 1917, Theremin wrote that Ioffe talked of electrons, the photoelectric effect and magnetic fields as parts of an objective reality that surrounds us every day, unlike others that talked more of somewhat abstract formulae and symbols. Theremin wrote that he found this explanation revelatory and that it fit a scientific – not abstract – view of the world, different scales of magnitude, and matter. From then on, Theremin endeavoured to study the microcosm, in the same way he had studied the macrocosm with his hand-built telescope. Later, Kirill introduced Theremin to Ioffe as a young experimenter and physicist, and future student of the university.
Theremin recalled that while still in his last year of school, he had built a million-volt Tesla coil and noticed a strong glow associated with his attempts to ionize the air. He then wished to further investigate the effects using university resources. A chance meeting with Abram Fedorovich Ioffe led to a recommendation to see Karl Karlovich Baumgart, who was in charge of the physics laboratory equipment. Karl then reserved a room and equipment for Theremin's experiments. Abram Fedorovich suggested Theremin also look at methods of creating gas fluorescence under different conditions and of examining the resulting light's spectrum. However, during these investigations Theremin was called up for military service as a result of World War I.
World War I and Russian Civil War
Although only in his second academic year, the deanery of the Faculty of Physics and Astronomy recommended that Theremin go to the Nikolayevska Military Engineering School in Petrograd (previously Saint Petersburg), which usually only accepted students in their fourth year. Theremin recalled that Ioffe reassured him that the war would not last long and that military experience would be useful for scientific applications.
Beginning his military service in 1916, Theremin finished the Military Engineering School in six months, progressed through the Graduate Electronic School for Officers, and attained the military radio-engineer diploma in the same year. In the course of the next three and a half years he oversaw the construction of a radio station in Saratov to connect the Volga area with Moscow, graduated from Petrograd University, became deputy leader of the new Military Radiotechnical Laboratory in Moscow, and finished as the broadcast supervisor of the radio transmitter at Tsarskoye Selo near Petrograd (then renamed Detskoye Selo).
During the Russian Civil War, in October 1919 White Army commander Nikolai Nikolayevich Yudenich advanced on Petrograd from the side of Detskoye Selo, apparently intending to capture the radio station to announce a victory over the Bolsheviks. Theremin and others evacuated the station, sending equipment east on rail cars. Theremin then detonated explosives to destroy the 120-meter-high antenna mast before traveling to Petrograd to set up an international listening station. There he also trained radio specialists but reported difficulties obtaining food and working with foreign experts whom he described as narrow-minded pessimists.
Theremin recalled that on an evening when his hopes of overcoming these obstructing experts reached a low ebb, Abram Fedorovich Ioffe telephoned him. Ioffe asked Theremin to come to his newly founded Physical Technical Institute in Petrograd, and the next day he invited him to start work at developing measuring methods for high-frequency electrical oscillations.
The day after Ioffe's invitation, Theremin started at the institute. He worked in diverse fields: applying the Laue effect to the new field of X-ray analysis of crystals, using hypnosis to improve measurement-reading accuracy, working with Ivan Pavlov's laboratory, and using gas-filled lamps as measuring devices. He built a high-frequency oscillator to measure the dielectric constant of gases with high precision; Ioffe then urged him to look for other applications using this method, and shortly made the first motion detector for use as a "radio watchman".
While adapting the dielectric device by adding circuitry to generate an audio tone, Theremin noticed that the pitch changed when his hand moved around. In October 1920 he first demonstrated this to Ioffe who called in other professors and students to hear. Theremin recalled trying to find the notes for tunes he remembered from when he played the cello, such as The Swan, by Saint-Saëns. By November 1920, Theremin had given his first public concert with the instrument, now modified with a horizontal volume antenna replacing the earlier foot-operated volume control. He named it the etherphone, but it was known in the Soviet Union as the Russian: Терменвокс, romanized: Termenvox or Termenvoks, in Germany as the Thereminvox and later, in the USA, as the theremin.
On 24 May 1924 Theremin married 20-year-old Katia (Yekaterina Pavlovna) Konstantinova, and they lived together in his parents' apartment on Marat street. In 1925 Theremin went to Germany to sell both the radio watchman and Termenvox patents to the German firm Goldberg and Sons. According to Glinsky, this was the Soviet's "decoy for capitalists" to obtain both Western profits from sales and technical knowledge.
During that time Theremin was also working on a wireless television with 16 scan lines in 1925, improving to 32 scan lines and then 64 using interlacing in 1926, and he demonstrated moving, if blurry, images on 7 June 1927. His device was the first functioning television apparatus in Russia.
After being sent on a lengthy tour of Europe starting 1927–including London, Paris, and towns in Germany – during which he demonstrated his invention to full audiences, Theremin went to the United States arriving on 30 December 1927 with his first wife Katia. He performed the theremin with the New York Philharmonic in 1928. He patented his invention in the United States in 1928 and then granted commercial production rights to RCA.
Theremin set up a laboratory in New York in the 1930s, where he further refined the theremin and experimented with other inventions and new electronic musical instruments. These included the Rhythmicon commissioned by the composer Henry Cowell.
In 1930, ten thereminists performed on stage at Carnegie Hall. Two years later, Theremin conducted the first-ever electronic orchestra, featuring the theremin and other electronic instruments including a "fingerboard" theremin which resembled a cello in use (Theremin was a cellist). In 1931, he worked with composer Henry Cowell to build an instrument called the rhythmicon. They were lucky to have gotten it to market as quickly as they did as brothers Otto and Benjamin Miessner had almost completed a similar instrument with the same name.