THE THEREMIN
What is a theremin? How does it work? Where have I heard it?
What is a theremin? Invented in Russia in 1919 by Lev Sergeyevitch Termen, it is one of the world's earliest electronic musical instruments and is the grandfather of today's modern synthesizers. While working as a Russian military scientist  in the oscillator laboratory at the Physico-Technical Institute in Petrograd (St. Petersburg), Termen was trying to develop a means to locate enemy radio transmitters for the military. One day while working with various gases in vacuum tubes he serendipitously noticed that the presence of his body could detune a radio receiver. Being a trained classical cellist, he realized the implications of his discovery and was soon playing several tunes for his scientific and military colleagues. He soon developed the first prototype for use as a musical instrument. Its creation opened up the whole field of electronic music that eventually led to the invention of the ondes Martenot, electronic organs, and today's synthesizers. The most unique feature of the theremin, however, is that it played without touching it! With carefully controlled hand gestures moving through two electromagnetic fields (one for volume, one for pitch), the thereminist is able to pluck music out of thin air--out of the "ether" so to speak-- hence one of the early names for this instrument, the aetherphone. Professor Termen's name was later anglicized to Leon Theremin, and his improved design became known as the Thereminvox. Finally the generic term "theremin" made its way into the musical lexicon to describe any of these instruments. The original theremins were comprised of special coils and vacuum tubes. Some of today's modern theremins use solid-state circuitry and are thus lightweight and much more portable. However, there is a strong desire among thereminists for the richness and authenticity of the old tube sound, so talented individuals currently undertake the task of research and development, and have had success in re-creating the historic theremin sounds and features using modern available tubes.
How does it work? The sound is produced by the interaction of two radio frequency oscillators which normally are operating above the range of human hearing. However, if one of these oscillators is slightly detuned by varying it's frequency while the other oscillator remains fixed, the difference in the frequencies (known as the beat frequency) is in the audible range and can be amplified. This process is known as heterodyning. The vertical pitch antenna controls the variable oscillator. The electromagnetic field which surrounds the pitch antenna can be changed by the proximity of the human hand, body, or other object placed within proximity of the pitch antenna. The human body possesses a stored electrical charge, which is called its capacitance. This body capacitance can disrupt the electromagnetic field of the pitch antenna, thus affecting the variable oscillator. The closer the hand gets to the antenna, the greater the effect, and, therefore, the higher the beat frequency and the higher the pitch. The farther the hand gets away from the antenna, the less effect of the body capacitance, and, therefore, a lower beat frequency and lower pitch. The pitch range (tessatura) can be adjusted for four, five, or sometimes more octaves. In addition the pitch can be tuned to allow for variations in playing distance from the pitch antenna (and thus the physical space between pitches) by increasing or decreasing it's sensitivity to body capacitance. The horizontal volume antenna, which is in the shape of a loop, also controls a high frequency oscillator, which when detuned by the proximity of the player's hand capacitance, lowers the sound volume. Moving the hand away from the volume antenna raises the volume. Carefully controlled up-and-down movement of the left hand (although the antennas may be reversed for left-handed thereminists) helps in the articulation of discrete notes as well as playing dynamics, crescendos, decrescendos, etc.
Where have I heard it? Early thereminists used the theremin for the performance of both classical and popular music. The greatest of these was the late Clara Rockmore who performed extensively in recitals and concerts for several decades, appearing with New York, Philadelphia, and other orchestras under such great conductors as Leopold Stokowski. Hollywood began to flirt with the theremin in the early 1940's. But it was in 1945 that the instrument received its biggest boost when composer Miklos Rozsa injected its mysterious and eerie sounds into his scores for Spellbound and The Lost Weekend. Later filmscores that used the theremin include The Spiral Staircase, The Red House, Rocketship X-M, The Day the Earth Stood Still, It Came from Outer Space, The Thing, The Delicate Delinquent, and many other science-fiction, horror, and suspense films. It was even used in The Ten Commandments for the plague scenes. Most of the theremin recording sessions at that time were performed by the late Dr. Samuel Hoffman. More recently the theremin has been used in such films as Ed Wood and Mars Attacks. Various pop/rock music groups have used the theremin from time to time, but contrary to a popular misconception, a theremin was NOT used by the Beach Boys in their hit song Good Vibrations. The instrument actually producing the theremin-like sound in that song was named an "electro-theremin," a moniker which undoubtedly contributed to the confusion. However, instead of using hand gestures in the air to control an oscillator, the electro-theremin used a contact switch that slid on a wire along a keyboard guide to mechanically control an oscillator. It was invented and performed by Dr. Paul Tanner, who was also a professor of jazz studies at UCLA and a studio trombonist for ABC. A modern re-creation of his instrument is known as a Tannerin.
Copyright © 1997-2023  Robert Froehner All Rights Reserved