What is a theremin?
The theremin was invented in 1920 by Russian scientist, cellist and spy Lev Sergeyevich Termen, or Leon Theremin as he was known in the US.
Surely the only instrument that is played without anyone touching it, its physics are simple: two antennae emit electrical fields and the player interrupts them with any part of their body. In general, the left hand controls volume while the right hand determines pitch.
Martinů wove moments of otherworldly tenderness into the otherwise bruising textures of his Fantasia for theremin, oboe, piano and string quartet.
The theremin also crops up in Fazil Say's Universe Symphony and Kalevi's Theremin Concerto.
Written between 1932 and ’34, Edgar Varèse’s Ecuatorial was one of the first pieces to mix electronic and traditional instruments. A Mayan invocation to the creative gods, the work’s premiere featured two theremins, although subsequent performances used ondes Martenot.
Gershwin’s pupil Joseph Schillinger wrote his 1929 First Airphonic Suite for Lev Termen, the inventor of the theremin – highly Romantic in style, the suite incorporates the instrument as naturally as if a cello or violin were the soloist.
Although not originally scored for the theremin, the Australian composer Percy Grainger’s theoretical Free Music Nos 1-4 suits them well, being written for an unnamed instrument of free, continuous pitch without rhythmic elements.
In the film world, meanwhile, the theremin has been used for eerie sci-fi sounds, most notably by Bernard Herrmann (The Day The Earth Stood Still), Howard Shore (Ed Wood), Danny Elfman (Mars Attacks) and, notably, Miklós Rózsa (Spellbound).
Find out more about the theremin and the virtuoso theremin player Carolina Eyck in the July 2020 issue of BBC Music Magazine.