Hjortur - Home - Links - Electronic Musical Instruments - Theremin 1917
			The principles of beat frequency or heterodyning oscillators were discovered by chance during the first decades of the twentieth century by radio engineers experimenting with radio vacuum tubes. Heterodyning effect is created by two high radio frequency sound waves of similar but varying frequency combining and creating a lower audible frequency, equal to the difference between the two radio frequencies (approximately 20 Hz to 20,000 Hz). the musical potential of the effect was noted by several engineers and designers including Maurice Martenot, Nikolay Obukhov, Armand Givelet and Leon (or Lev) Sergeivitch Termen the Russian Cellist and electronic engineer. Termen's first machine, built in the USSR in 1917 was christened the "Theremin" (after himself) or the "Aetherophone" (sound from the 'ether') and was the first instrument to exploit the heterodyning principle A Video of the Theremin(2.4mb Quicktime file)
	Lev Sergeivitch Termen playing the "Theremin"