Science history: the man who made the first electronic instrument
Leon Theremin was an inventor, a musician, and a spy. Jeff Glorfeld reports.
With the world in the grip of the Cold War in the 1950s, movie makers responded with a clutch of topical science fiction films destined to become classics, including titles such as The Thing From Another World, and The Day The Earth Stood Still, in 1951, and Forbidden Planet in 1956.
Central to crafting moods of doom and dread were the soundtracks to these pictures, all of which featured an instrument called a theremin, its tremulous tones themselves often described as “otherworldly”.
Frequently called the world's first electronic instrument, the theremin was invented by Russian scientist Leon Theremin (or to give him his formal Russian name, Lev Sergeyevich Termen), who toured the world in the 1920s, ’30s and beyond, giving concerts and displaying his creation.
Although his success as an inventor and musician were well recognised during his lifetime, what was not known until much later was that Theremin was also employed by the feared Soviet spy agency NKVD, precursor to the KGB.
Theremin was born in Saint Petersburg, Russia, in 1896. In school he studied physics and astronomy, along with the cello and music theory.
In 1919, while working as head of the laboratory of electrical oscillators in the Physico-Technical Institute in the city, at that stage renamed Petrograd, he researched proximity sensors for the Russian government, using an electromagnetic field to detect objects that entered a certain zone.
Instead of creating a land-based sonar device, he came up with a musical instrument.
He did so because he noticed that when he moved his body in or out of an electromagnetic field produced by a radio frequency oscillating circuit, he changed its frequency. A keen cellist in his spare time, Theramin wondered how this phenomenon – which relied on the ability of the human body to hold an electrical charge, a quality known as capacitance – could be exploited.
In 1989 Theremin told musicologist Olivia Mattis: “I conceived of an instrument that would create sound without using any mechanical energy, like the conductor of an orchestra.”
The result was an unusual looking electronic device with two primary circuits: one controlling pitch and the other volume. The pitch circuit used two tuned radio frequency oscillators, one fixed and the other variable. The first generated waves at a static frequency. The second was capable of producing a range of frequencies and was connected to a vertical antenna.
Through a process called heterodyning, signals from the two oscillators were mixed together. The frequency of one was subtracted from the other – and the remainder amplified to produce a musical tone.
The New York Times, in its obituary for Theremin, published on 9 November 1993, explains that a theremin “looks like a radio receiver with a vertical antenna on top and a horizontal metal loop on the side. It is played by moving the right hand in the air near the antenna.
“The pitch varies according to the hand's distance from the antenna. The volume is controlled by moving the left hand back and forth in front of the metal loop. In effect, it was the first synthesiser.”
Theremin, with the blessing of the Soviet Kremlin, took his invention on a world tour, eventually settling in the US. In 1929 he sold the patent to American electronics giant RCA.
In 1938 he returned to the Soviet Union, where he was convicted of anti-Soviet propaganda and sentenced to seven years' imprisonment in a Siberian gulag. Some sources say he was kidnapped, others that he returned voluntarily.
When Soviet authorities realised Theremin’s value, however, he was put to work developing eavesdropping systems and other electronic devices, which were used extensively by the KGB.
One in particular is an incredible story. In August 1945, with the Second World War over in Europe, a group of boys from a Soviet youth organisation travelled to the US embassy in Moscow, carrying a hand-carved plaque of the great seal of the USA, which they gave to W. Averell Harriman, the US ambassador.
Harriman accepted the gift and hung it in the study of his Moscow residence.
What Harriman did not know what that the seal contained a sophisticated listening device, developed by Theremin. The device, later known as “The Thing”, would not be discovered until 1952.
Theremin died in Moscow in 1993 at the impressive age of 97.