πTon/2 is a sound installation that intervenes in the continuity of the researches of Cod.Act on mechanical and sound organicity. It results from an experience on the deformation of an elastic form and its incidence on the evolution of a musical work. The object is a flexible ring closed on itself. It is set in motion by torsional engines located inside its body. πTon, by twisting and waving on itself, moves in a very natural and unpredictable way.