A cheap and usefull tool for phonography and sound installations...

Piezo-electricity is the aptitude of a material to produce voltage when it is bent.
And inversely when a voltage is applied, a deformation happens.

Piezo transducers can act as microphone as well as speakers. But unsual microphones and speakers...

Snow melting under two piezo, in Parc du Mercantour, France, 07.06.02. 

On a branche under the rain, at Col de Vence. 

The metal structure of a bed, with loosing springs moving under the wind. Found behind a deserted stone house at Plateau de Caussols, France. Drawing by Wan-Shuen.

Two trees rubbing each other and squeaking. 

A piezo transducer attached to a wind blown metal wire.