A sound absorber can include a housing including a back wall, a perimeter wall, and an interior wall that form cells having cavities. The sound absorber can also include a panel disposed on the housing that substantially faces the back wall and encloses the cavities of the cells. The panel can define groups of holes for each cell such that one group of holes extend though the panel to the cavity of one cell and another group of holes extend through the panel to the cavity of another cell.

An acoustic insulation product includes a panel made of porous material, based on foam or fibres, including a first face, referred to as back face, intended to face towards a wall, and a second face, referred to as front face, situated on the opposite side to the back face, and a layer, referred to as backing layer, which adheres to or is linked or coupled at least in part to the back face of the panel made of porous material, the backing layer having an airflow resistance of between 5 kPa.Math.s/m and 20 kPa.Math.s/m.

An acoustic panel (for absorbing sound) includes a first sheet with spaced microperforations, a second sheet with microperforations more widely spaced than the microperforations of the first sheet, and a first cellular core sandwiched between the first sheet and the second sheet. The panel can be spaced from a surface, such as a wall. A second cellular core can be provided between the second sheet and a third sheet. The third sheet is preferably solid without microperforations but can have microperforations. Noise Reduction Coefficient (NRC) can be 0.8.

In a sound absorption panel formed by stacking a plate perforated with a hole having a hole size smaller than a fiber length such as expanded metal, a honeycomb material, and felt-like fiber between the perforated plate and the honeycomb material, and joining the perforated plate, the felt-like fiber, and the honeycomb material to each other with an adhesive, the adhesive applied to the perforated plate is permeated into a surface of the felt-like fiber exposed from the hole to fix the fiber on the surface.

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 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 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.

An example acoustic tile is disclosed having a structure with at least one layer. A plurality of openings are formed in the at least one layer of the structure. The openings are configured to direct sound waves hitting the structure in multiple different directions through the at least one layer to absorb a majority of the sound waves and inhibit the sound waves hitting the structure from reflecting off of the structure. In an example, the openings are juxtaposed, different sizes, different orientations, and/or different numbers of openings on separate layers.

A panel coating system for simple and efficient installation of a removably attachable layer to a panel.

Provided is a soundproof structure that can obtain high soundproofing performance and suitably maintain characteristics of a forming material. A soundproof structure includes: a microperforated sheet having a plurality of through-holes penetrating in a thickness direction, in which an average opening diameter of the through-holes in a main surface of the microperforated sheet is 0.1 m or more and less than 100 m, at least some of the plurality of through-holes are a through-hole A that has a shape having an internal maximum hole diameter, and in the through-hole A, assuming that a minimum hole diameter is .sub.1 and a maximum hole diameter is .sub.2, 1<.sub.2/.sub.15 is satisfied.