The Theremin was developed by Lev Sergejewitsch Termen (1896–1993), a Russian Professor of Physics. The Name originates from the inventor himself, who lived in Europe under the name of Leon Theremin.
The Theremin is played by holding the hands above/aside the antennas. The spacing between the antenna and the hand defines the volume, while the other hand defines the tone the instrument creates.
The Theremin can create tones up to 9 octaves.
Earlier versions of the instrument usually required tube oscillators, while the modern versions use transistor oscillators.
Jonsu played the Theremin in the tracks Valoissa and Sanoja. She played the instrument live at Tavastia Helsinki on September, 27th, 2008