In the last three years, we have attempted to sketch the random panorama of contemporary "sound arts". For those directly concerned, such a heuristic phrase can federate as much as it can divide. The listening process, whether it be physical, distracted or critical, unaware of its own habituation, sometimes even define the status of an artist. This fourth selection MUSIC NO MUSIC aims to explore the variations on musicality; its criteria, its limits, its vocabulary. In an area still to be outlined, should one opt for the traditional posture of musicology and wonder about tone, rhythm or language? Will the underlying attraction towards the sublime and virtuosity always counteract D.I.Y processes? Could we embrace the principles of Cage, Schaeffer, the Dada and Punk energies to constantly challenge our judgement automatisms and tend towards audacious shapes and structures?... Each of the present artists, through the formal or conceptual decisions bordering his creative gesture, adds a fragment to the global answer. Often enlightened, fortunately subjective.