A noise reduction apparatus can include a frame and multiple spaced apart panels positioned adjacent to each other. Each of the panels or only one of the spaced apart panel elements may have holes therein to receive acoustic waves for absorbing the waves between the panels. The panels can be attached to a frame or other connection structure so that the arrangement of panels can be hung over a work space or positioned in a work space (e.g. in a wall, formed as a partition or wall, included as part of shelving, etc.). The panels can also be incorporated into a light fixture that may hang from a ceiling or be attached to some other type of support (e.g. a table, a base, etc.). The panels can be composed of glass, wood, or other type of material.

A panel with one or more perforations, having a front surface, wherein the contrast Cm between the front surface and the one or more perforations is less than 0.3, a sound absorbing system including a panel and a masking layer, wherein the masking layer is air permeable, and the use of the panel or the sound absorbing system.

A soundproof structure has at least one soundproof cell including a frame having a hole portion and a film fixed to the frame so as to cover the hole portion. The soundproof cell is disposed in an opening member having an opening in a state in which a film surface of the film is inclined with respect to an opening cross section of the opening member and a region serving as a ventilation hole, through which gas passes, is provided in the opening member.

A soundproof structure has a plurality of soundproof cells arranged in a two-dimensional manner. Each of the plurality of soundproof cells includes a frame formed of a frame member forming an opening and a film fixed to the frame. Two or more types of soundproof cells having different first resonance frequencies are present in the plurality of soundproof cells. A shielding peak frequency at which transmission loss is maximized is present within a range equal to or higher than a lowest frequency among first resonance frequencies of the soundproof cells and equal to or lower than a highest frequency among the first resonance frequencies of the soundproof cells.

The present invention provides a sound attenuating apparatus including a substrate element comprising at least one first heterogeneous material, and at least one region comprising at least one further heterogeneous material at least partially located in the substrate element, wherein the at least one further heterogeneous material has at least one more scale of heterogeneity than the at least one first heterogeneous material. The present invention provides a method and apparatus for attenuating sound through a cavity construction in buildings and vehicles or the like, wherein the method comprises locating at least one region of adsorptive material in a cavity defined between a first wall region and a further wall region to attenuate sound transmission across the wall regions.

Sound absorbing material for use in rooms inside buildings. The material comprises a continuous polymeric film (11) having smooth surfaces, said film having a thickness (t) of about 0.1 to 0.3 mm. The film is provided with numerous substantially parallel discontinuous microslits (12) with a degree of perforation of from 0.3-3%. The microslits are cut with laser devices to produce a highly smooth and level surface. The film is tensioned in a frame (16) with a level film surface or curved film surface.