The Theremin and the Dawn of Electronic Instruments — An Instrument Played Without Touch

A Qualitative Turning Point in the History of Instruments

For 40,000 years, the history of musical instruments was a history of making sound through physical vibration. Plucking strings, blowing breath into pipes, striking membranes or plates. But in the 20th century, an entirely different principle emerged — making sound directly with electricity. This is the fifth family added later to the Hornbostel-Sachs classification system: the electrophone.

Its first practical example was not a keyboard instrument at all, but a strange instrument that didn’t even have a keyboard.

The Theremin (1920) — Played Without Touch

Leon Theremin (1896-1993) was a Russian physicist. As a byproduct of his research into vacuum tubes, he invented in 1920 an instrument that could be played in mid-air without ever being touched.

• Bringing a hand near one of the two antennas changes its electrostatic capacitance
• One antenna controls pitch, the other controls volume
• The performer simply moves their hands through the air, never touching the instrument at all

Its sound is a wavering, continuous tone that resembles neither a human voice nor a violin. It became known as a sound effect in science-fiction and horror films, and was even used in the Beach Boys’ “Good Vibrations” (strictly speaking, a similar instrument). The Theremin showed the world that “electricity could become sound” — the origin point of electronic instruments.

The Ondes Martenot (1928) — A Keyboard Is Added

A few years after the Theremin, the Frenchman Maurice Martenot invented the Ondes Martenot. Like the Theremin, it used vacuum-tube oscillation, but it allowed pitch to be controlled with a keyboard and a ribbon (slid along with a ring). Its performance was far more reproducible, and it became a favorite among classical composers.

• Olivier Messiaen’s Turangalîla-Symphonie (1948) is its most famous use
• Its tone is mysterious and song-like, and it’s still used today in contemporary music and film scores

Where the Theremin was an experiment in “not touching,” the Ondes Martenot took a step toward the electronic keyboard by connecting the traditional keyboard interface to an electronic instrument.

The Hammond Organ (1935) — Synthesizing Overtones

The Hammond organ, released by Laurence Hammond in 1935, marked an important turning point in the history of the electronic keyboard.

• Tonewheels — gear-shaped metal discs rotate, and an electromagnetic pickup picks up the sound they generate
• Drawbars — sliders mix the amount of each overtone to shape the timbre (the prototype of additive synthesis)
• It was sold to churches and homes as a substitute for the pipe organ, but it eventually became a leading voice in jazz, gospel, and rock

The B-3 model in particular, paired with a rotating speaker (the Leslie), produced a distinctively swirling sound that was beloved by Jimmy Smith (jazz), Deep Purple (rock), and others. The idea of “shaping timbre by mixing overtones” connects directly to how synthesizers would later create sound.

Establishing the Idea of “Making Sound with Electricity”

The three instruments of this early era each demonstrated a different approach:

Instrument	Year	Principle	Interface
Theremin	1920	Vacuum-tube oscillation	Hands in the air (no touch)
Ondes Martenot	1928	Vacuum-tube oscillation	Keyboard + ribbon
Hammond organ	1935	Tonewheel + electromagnetic pickup	Keyboard + drawbars

What they had in common was that none had a physical resonating body — they generated electrical signals and sounded them through a speaker. With this idea firmly established, the next era began in earnest: the full-scale development of “keyboard instruments that make sound with electricity.”

That said, the instruments of this early era had not yet reached the stage of being able to freely design sound. What made that possible was, first, the electric piano, which electrically amplified mechanical vibration, and then the synthesizer, which synthesized sound with voltage.

In the next article, before we get to synthesizers, we’ll trace the world of the electric piano — Fender Rhodes, Wurlitzer, and Clavinet — the instruments that shaped the sound of popular music.