An acoustic-metamaterial acts as a sound reducing filter in that the level of sound that exits the structure is much less than the magnitude of sound that enters the structure. In forming the structure, modular stages of a given geometry are stacked upon one another to create a cell. Each stage of the cell is provided with a nozzle that is acoustically connected to the nozzles of other stages of the cell. The stages have chambers that are positioned radially or laterally outside of the respective nozzles, with the chambers of the cell being acoustically connected to one another. An amalgamation of cells are arranged in an adjacent formation, with chambers of the cells being acoustically connected to one another for purposes of protecting items, components and people from destructive levels of sound.

An acoustic-metamaterial acts as a sound reducing filter in that the level of sound that exits the structure is much less than the magnitude of sound that enters the structure. In forming the structure, modular stages of a given geometry are stacked upon one another to create a cell. Each stage of the cell is provided with a nozzle that is acoustically connected to the nozzles of other stages of the cell. The stages have chambers that are positioned radially or laterally outside of the respective nozzles, with the chambers of the cell being acoustically connected to one another. An amalgamation of cells are arranged in an adjacent formation, with chambers of the cells being acoustically connected to one another for purposes of protecting items, components and people from destructive levels of sound.

A pneumatic pump silencer including a body defining an inner volume and having at least one wall including an air outlet orifice, and an attenuating pad having a face arranged across from the air outlet orifice, wherein a gap is arranged between the face of the attenuating pad and an outer face of the wall including the air outlet orifice, the thickness of the gap being between 0.5 mm and 5 mm.

A pneumatic pump silencer including a body defining an inner volume and having at least one wall including an air outlet orifice, and an attenuating pad having a face arranged across from the air outlet orifice, wherein a gap is arranged between the face of the attenuating pad and an outer face of the wall including the air outlet orifice, the thickness of the gap being between 0.5 mm and 5 mm.

A sizing composition for insulating products based on mineral wool, in particular glass or rock wool, which includes at least one ammonium lignosulfonate or alkali metal or alkaline earth metal salt of lignosulfonic acid, and at least one carbonyl compound of formula: R—[C(O)R.sub.1].sub.x (I) in which: R represents a saturated or unsaturated and linear, branched or cyclic hydrocarbon radical, a radical including one or more aromatic nuclei which consist of 5 or 6 carbon atoms, a radical including one or more aromatic heterocycles containing 4 or 5 carbon atoms and an oxygen, nitrogen or sulfur atom, it being possible for the R radical to contain other functional groups, in particular hydroxyl or alkoxy groups, especially methoxy groups, R.sub.1 represents a hydrogen atom or a C.sub.1-C.sub.10 alkyl radical, and x varies from 1 to 10.

A sizing composition for insulating products based on mineral wool, in particular glass or rock wool, which includes at least one ammonium lignosulfonate or alkali metal or alkaline earth metal salt of lignosulfonic acid, and at least one carbonyl compound of formula: R—[C(O)R.sub.1].sub.x (I) in which: R represents a saturated or unsaturated and linear, branched or cyclic hydrocarbon radical, a radical including one or more aromatic nuclei which consist of 5 or 6 carbon atoms, a radical including one or more aromatic heterocycles containing 4 or 5 carbon atoms and an oxygen, nitrogen or sulfur atom, it being possible for the R radical to contain other functional groups, in particular hydroxyl or alkoxy groups, especially methoxy groups, R.sub.1 represents a hydrogen atom or a C.sub.1-C.sub.10 alkyl radical, and x varies from 1 to 10.

A variable acoustic assembly comprising a housing and a one or more absorbing pads. The housing contains the one or more absorbing pads, a one or more doors, a one or more rear brackets, and a one or more hinges. The one or more doors attach to the one or more rear brackets with the one or more hinges. The one or more doors are configured to selectively open and selectively close between an open configuration and a closed configuration by rotating on the one or more hinges. The variable acoustic assembly having a closed width in the closed configuration and an open width in the open configuration. With the one or more doors in the open configuration, a portion of the one or more absorbing pads are exposed outside of the housing.

A laminated structure for use in retrofit building construction (partition, wall, ceiling, floor or door) that exhibits improved acoustical sound proofing characteristics while being optimized for efficient installation. The laminated structure includes a panel with at least one layer of viscoelastic glue, or fire-10 resistant, viscoelastic glue, which functions both as a glue and an energy dissipating layer. In one embodiment, the laminated structure to be attached to an existing wall in some embodiments includes standard paper-faced gypsum board. In another embodiment the to-be-applied laminated structure includes a cement-based board, and in yet another embodiment the to-be-applied laminated 15 structure includes a cellulose-based board. Once the laminated structure is installed on an existing wall or other partition, the resulting structure greatly attenuates transmitted noise and minimizes the labor required for installation and finishing.

The present invention discloses a sound absorption material including an organic frame material; a binder; a thickener; and a plurality of sound absorption grains attached to the organic frame material via the binder, having a grain size in a range of 10-100 μm. The stability and the sound absorption performance of the sound absorption material have been effectively improved.

The present invention discloses a sound absorption material including an organic frame material; a binder; a thickener; and a plurality of sound absorption grains attached to the organic frame material via the binder, having a grain size in a range of 10-100 μm. The stability and the sound absorption performance of the sound absorption material have been effectively improved.