The Theremin: Music Played Without Touching Anything

Read the episode (Narration script)

Welcome to Origins. In this program we explore the technological and scientific roots of the modern world. Let's begin.

Petrograd, the autumn of 1920. Russia's civil war is not yet over, and the city is short of food and fuel. In a laboratory at the Physico-Technical Institute, a twenty-four-year-old physicist named Lev Termen is wearing headphones and listening to a gas.

His director, Abram Ioffe, has him working on ways to measure the properties of gases with radio circuits. The setup is simple in outline. Put the gas between two metal plates, and those plates become part of a circuit that oscillates far faster than any sound. Warm the gas or change its pressure, and the oscillation shifts by a tiny amount.

The trouble is reading a shift that small. A needle on a dial barely moves. So Termen borrows a trick from radio. He builds a second oscillator, fixed and steady, and mixes the two signals together. Anyone who has heard two piano strings slightly out of tune knows what happens next. The two tones produce a slow wobble, a beat, at the difference between them. Do the same with two radio frequencies, each far too high to hear, and the difference can land squarely in the range of human hearing. A change in the gas becomes a change in pitch.

Then he notices something that has nothing to do with the gas. When his hand moves near the circuit, the note slides up. When he pulls it away, the note falls.

The explanation is ordinary physics. A human body is mostly salt water, and it conducts. A hand near a wire behaves like one more metal plate, storing a trace of electric charge, and that trace is enough to retune the oscillator. It is the kind of interference an experimenter normally shields against. But Termen had trained as a cellist at the conservatory. He stood there and started hunting for melodies.

He showed Ioffe, who called in the rest of the institute, and by his own later account the room gave him an ovation. That November he played his first public concert, for a hall of engineering students.

The instrument that came out of this is strange to look at even now. A wooden cabinet, a straight metal rod standing up on the right, a metal loop sticking out sideways on the left. The right hand moves toward the rod to raise the pitch. The left hand hovers over the loop to control loudness, and the closer it gets, the quieter the sound. Nobody touches anything. As his American patent would later put it, the operator's hands are not required to make physical contact with the instrument.

That is also what makes it brutally hard to play. There are no keys, no frets, no string under the finger. The notes are locations in empty air, and since the player's whole body is part of the circuit, swaying to the music will bend the pitch.

Termen saw other uses at once. The same circuit made a burglar alarm, a so-called radio watchman that whistled when someone came within a few meters. In 1922 he was invited to bring both versions to the Kremlin. He played Glinka's "The Skylark," and then Lenin wanted a turn. Termen recalled, decades later, guiding his hands at first, then letting go, and Lenin finishing the tune alone. Lenin approved a tour. A machine that pulled music out of the air made a fine advertisement for electrifying the country.

The tours reached Western Europe in 1927, and at the very end of that year Termen landed in New York, where his name became Leon Theremin. The patent was granted in February 1928. RCA licensed the design and in 1929 sold it in a mahogany cabinet for one hundred seventy-five dollars, tubes and loudspeaker extra, on the promise that anyone who could hum a tune could play it.

That promise was not true, and the stock market crashed that autumn. RCA built about five hundred. What rescued the instrument's reputation was one player, Clara Rockmore, a former violin prodigy who worked out a system of fingering in the air, fast and exact enough for the concert repertoire.

Theremin himself piled up debts. In 1938 he left New York aboard a Soviet freighter, leaving behind his creditors and his wife, the dancer Lavinia Williams. Why he went is still argued over. What happened next is not. He was arrested within months, convicted in 1939, and sent to the labor camps of Kolyma in the far northeast. Then, like other engineers the state had imprisoned and found it needed, he was pulled back to a guarded laboratory in Moscow.

There the hand-and-wire idea turned up again, in a different form. In 1945, Soviet schoolchildren presented the American ambassador with a carved wooden Great Seal of the United States. It hung in his study in Moscow for years. Inside was a small metal chamber with a membrane a few thousandths of a millimeter thick and a short antenna. No battery. No wires. It did nothing at all until a radio beam was aimed at the building from outside. Then voices in the room shook the membrane, the membrane changed the chamber's electrical capacity, and the radio waves bouncing back carried the conversation.

An American technician found it in September 1952 while sweeping the room for signals, and it came to be called the Thing. The design is credited to Theremin. In his instrument, a moving body shifts a capacitance and the result is sound. In the Thing, sound shifts a capacitance and the result is a radio signal. It is the same physics, run in the opposite direction.

The musical line continued without him. In 1949 a teenager in Queens named Robert Moog built a theremin from magazine plans. At nineteen he published his own design and began selling kits with his father. About a decade later he built the synthesizer that carries his name, and he credited the theremin as the place it started.

Theremin lived long enough to see some of this. He returned to the United States in 1991, at ninety-five, and died in Moscow two years later.

One piece of his discovery is now so common that it goes unnoticed. A phone screen does not feel pressure. It measures the small electrical change a fingertip makes as it arrives, the same effect that bent a note in a Petrograd laboratory.

People had built circuits to study the world, and one of them found that he was part of the circuit.

Thanks for listening to Origins.