Mat in sheets composed of granules and selected SBR rubber combined with polyurethane resins (MDI) with a density of 720kg/m3. The material has got an optimal elasticity and mechanic resistance that assures long life and constant acoustic performances. Impact sound insulation on floors with floating screed or dBred Piano Zero under flooring system with elastic layer directly glued under ceramic or wooden floorings. It can be used for the vibration isolation interposing it among planar surfaces.