A soft boundary structure is implemented using a resonator structure capable of receiving sound or vibration, establishing resonance coupled with received sound or vibration, and creating a reflection with a pi phase factor. A soft boundary is located on or closely adjacent the resonator structure. The soft boundary cooperates with the resonator structure to attenuate the sound or vibration.

An assembly forming an acoustic insulator having a first sheet, a pierced second sheet, and a plurality of first and second structures. Each first structure comprises a first and a second strip, wherein each is shaped to form half of the wall of a cage and wherein, for two successive halves, each strip comprises a facet of a joining wall. Each second structure is made up of a first and a second strip, wherein each is shaped to form half of the wall of a cone, wherein. For each strip, at least one of the wall halves of each cone is pierced. For two successive halves, each strip comprises one facet of the connecting wall. Each cone is located in a cell and each connecting wall is located between the two facets of a joining wall, and, between two adjacent first structures, a second structure is likewise fitted.

To provide a sound insulation sheet member which is excellent in sound insulation performance in a low frequency band and which has a compact configuration. A sound insulation sheet member 1 including a substrate 2 and a concavo-convex structure 3 placed on at least one surface of the substrate 2, in which the concavo-convex structure 3 is provided by repeatedly arranging a plurality of units each defined as a concavo-convex unit shape 4 including a linear convex portion 5, in one direction at substantially constant intervals on the surface of the substrate 2.

An object of the present invention is to provide a sound insulating sheet member that has high sound-insulating performance which exceeds mass law while being relatively light weight, that is highly flexible in design, excellent in versatility, and easy to manufacture so that productivity and economic efficiency can be improved, and a sound insulating structural body or the like using the same. The object thereof is achieved by using a sound insulating sheet member comprising at least a sheet having rubber elasticity and a plurality of resonant portions, wherein the resonant portions are provided in contact with a sheet surface of the sheet, each of the resonant portions including a base part and a weight part, and the weight part being supported by the base part and having a larger mass than the base part.

An object of the present invention is to provide a sound insulating sheet member that has high sound-insulating performance which exceeds mass law while being relatively light weight, that is highly flexible in design, excellent in versatility, and easy to manufacture so that productivity and economic efficiency can be improved, and a sound insulating structural body or the like using the same. The object thereof is achieved by using a sound insulating sheet member comprising at least a sheet having rubber elasticity and a plurality of resonant portions, wherein the resonant portions are provided in contact with a sheet surface of the sheet, each of the resonant portions including a base part and a weight part, and the weight part being supported by the base part and having a larger mass than the base part.

An object of the present invention is to provide a sound insulating sheet member that has high sound-insulating performance which exceeds mass law while being relatively light weight, that is highly flexible in design, excellent in versatility, and easy to manufacture so that productivity and economic efficiency can be improved, and a sound insulating structural body or the like using the same. The object thereof is achieved by using a sound insulating sheet member comprising at least a sheet having rubber elasticity and a plurality of resonant portions, wherein the resonant portions are provided in contact with a sheet surface of the sheet, each of the resonant portions including a base part and a weight part, and the weight part being supported by the base part and having a larger mass than the base part.

An acoustic panel is provided that includes a first skin, a second skin and a core structure. The core structure is connected to and forms a plurality of cavities between the first skin and the second skin. The cavities include a first cavity and a second cavity. The first cavity is fluidly coupled with one or more first perforations in the first skin. The second cavity is fluidly coupled with one or more second perforations in the second skin.

An alternating clockwise and counterclockwise helicoid cell structure for use in acoustic panels. The cell structure geometry may be easily replicated and tiled using additive manufacturing. The cell structure has at least an outer cavity and an inner cavity. The cavities are coaxial, share the same height, same entrance side, and same cell structure floor. The inner cavity includes a number of equal-volume inner chambers rotated uniformly in a first direction around the shared central axis; and the outer cavity includes a second number of equal-volume outer chambers rotated uniformly in an opposite direction to the first direction around the shared central axis. In various embodiments, one or more perforated baffles may extend, internally, across a chamber, perpendicular to direction of sound waves at the location of the perforated baffle. In various embodiments, one or more port openings from the outer cavity to the inner cavity may be present.

A circular multi-panel acoustic baffle assembly for suspending above an occupied space, the assembly including a plurality of baffle panel units each radiating away from a common center and generally lying in a vertical plane, upper edges of the baffle panel units lying in a common imaginary surface of revolution about the center, the baffle panel units being joined by common inner and outer arcuate ribs concentric with the center, radially inner ends and radially outer ends of the baffle panel units lying on imaginary circles concentric with the center.

A circular multi-panel acoustic baffle assembly for suspending above an occupied space, the assembly including a plurality of baffle panel units each radiating away from a common center and generally lying in a vertical plane, upper edges of the baffle panel units lying in a common imaginary surface of revolution about the center, the baffle panel units being joined by common inner and outer arcuate ribs concentric with the center, radially inner ends and radially outer ends of the baffle panel units lying on imaginary circles concentric with the center.