Prepared Piano by John Cage

Prepared piano is a special piano that John Cage modified in order to produce a different piano sound. The idea was to interfere with the normal vibration of the strings of the piano putting screws and object on the strings.

4' 33' by john Cage

What is silence?
After few years of music composition and noise experiments John Cage made the piece 4'33'.
The piece is 4 minutes and 33 second of silence.
John Cage arrive to the conclusion that is more important what happen around the performance - with all the non intentional sounds - than the composition itself. In this case john Cage defines the silence as the absence of composition, shifting the production of music from the physical expression to that of the natural sound produced by the surrounding.

The perfect noisy silence

This is the physical experiment which proofs that
in absence of air there is no sound.

But, the complete silence is almost impossible to experience. As John Cage said, there is always something to see and to hear. He also said that even in one of this special anechoic chambers - a room designed in order to avoid any sort of echoes - he was able to hear two sound: his nervous system in action and his blood in circulation. So, only when we die we will experience the real silence.