Thermofona is an interactive, digitally controlled, thermo-acoustic sound sculpture.Four infrared motion sensors trigger digital controls to heat electrical resistance wires. The resulting sound and volume resemble those of organ pipes. During play the hot wires glow orange in the glass tubes. 
Continually triggered by motion sensors, delayed-action crescendos and de-crescendos produce cycles of individual notes, merging intervals and chords. Some of these new combinations are programmed, while others occur at random. The hot air in the tubes renders the pitch slightly unstable, which creates ever new interferences. The interacting tubes also produce overtones that shift according to the listener's position, and create a spheric spatial sound.