Abstract: A sound control apparatus capable of improving the quality of the reproduction sound output from an electronic apparatus includes a sound control mat, and a support unit for supporting an electronic device having a speaker on the sound control mat. The sound control mat has a sound controlling structure configured to control the resonance of sound output from the speaker of the electronic apparatus when it is supported by the sound control mat. With this sound control apparatus, it is possible to enjoy a good tone directly output from a television, a stereo system or any other device having a small speaker without needing a special devising.

Abstract: An acoustic dampener (100) comprising a base member (101) having a first surface (102) and a second surface (103), the first surface (102) and the second surface (103) are spaced apart from each other defining a thickness (104) therebetween. The acoustic dampener (100) further comprising a pair of side arms (105), each having a first end (109) and a second end (110). Each side arm (105) is attached to the base member (101) at its first end (109) at a predetermined angle. The side arm (105) extends from the base member (101) to form a channel formation (119) to receive a batten. A flange (106) extends substantially orthogonally from the second end (110) of each side arm (105) for retaining a batten within the channel formation (119).

Abstract: A method for producing a double-layer or triple-layer sound-absorbing panel (10) is specified, said panel consisting of a support panel (20) and at least one cover panel or coating (30, 35) of the support panel (20), the cover panel or coating (30, 35) being fixedly connected to the support panel (20). In this case, an open-pore (121) support panel is provided as the support panel (20) and the sound-absorbing panel (10) is arranged on each side (12, 13) provided with a cover panel or coating (30, 35) with a device opposing said side emitting a laser beam, the upper face (12) of said panel (10) being subjected to the laser beam, which is designed to burn away material from the cover panel or coating (30, 35) facing said laser beam over the depth in the direction of the laser beam in a plurality of holes (31).

Abstract: A phononic device is provided suitable for attenuating mechanical vibration, as well as acoustic vibration that propagate through a medium. Through the periodic inclusion of domains of a material in a matrix that vary in the ratio of the longitudinal speed of sound (CL) and the transverse speed of sound (CT) between the domains and the matrix of equal to or greater than 2.0 and 40, respectively; improved significant attenuation of vibration is achieved.

Abstract: An acoustic barrier structure can include a support structure that defines a plurality of cells, a weight attached to the support structure, and at least one resonant membrane covering one of the plurality of cells. The at least one resonant membrane can comprise at least one weight. The at least one resonant membrane can have an anti-resonant frequency and the support structure with the weight can provide wide frequency band gaps between odd resonance modes while suppressing structure-membrane coupled modes to enable the anti-resonance of the at least one resonant membrane.

Abstract: An acoustic insulator having a tortuous path located in its interior.

Abstract: An inlet for an aircraft engine nacelle having an acoustic barrel panel, a septum buried or sandwiched within the acoustic barrel panel, and a perforated face sheet. The inlet may be located forward of an engine and/or an engine fan housed within the aircraft engine nacelle. Both the septum and the perforated face sheet may have perforations or holes therein of varying sizes and varying distances apart from each other. The smaller the area of the perforations or holes and the further apart they are from each other, the higher the impedance of a given area of the septum or the perforated face sheet. The impedance of the septum and/or the perforated face sheet may progressively increase in a direction away from the engine fan.

Abstract: A sound attenuating trim part, including at least one insulating area with an acoustic mass-spring characteristics having at least a mass layer and a decoupling layer adjacent to the mass layer, whereby the mass layer consists of a porous fibrous layer and a barrier layer, with the barrier layer being located between the porous fibrous layer and the decoupling layer and all layers are laminated together, and whereby the porous fibrous layer at least in the insulating area has adjusted dynamic Young's modulus (Pa) such that the radiation frequency of is at least 3000 (Hz).

Abstract: A matrix or array of elongated tubular members, each member being formed by spirally winding a piece or pieces of material into a generally cylindrical shape, wherein the matrix or array is mounted in an airflow to reduce the noise associated with and/or produced by the airflow.

Abstract: A hybrid acoustic absorption and reflection resonator can includes a rigid structure defining a cell, a membrane with at least one orifice attached to the rigid structure, and a back sheet attached to the rigid structure and covering the cell. The membrane is configured to reflect acoustic waves in a predetermined range of frequencies. The rigid structure, the membrane, and the back sheet define a Helmholtz cavity; the Helmholtz cavity is configured to absorb acoustic energy at a frequency within the predetermined range of frequencies.

Abstract: A device with simultaneous negative effective mass density and bulk modulus has at least one tubular section and front and back membranes sealing the tubular section. The front and back membranes sealing the tubular sections seal the tubular section sufficiently to establish a sealed or restricted enclosed fluid space defined by the tubular section and the membranes, and restrict escape or intake of fluid resulting from acoustic vibrations. A pair of platelets are mounted to the membranes, with the individual platelets substantially centered on respective ones of the front and back membranes.

Abstract: A composite batt structure that forms an effective low frequency sound absorber for use in buildings, appliances, automotive vehicles, and the like. The composite structure uses a facer covering a batt comprised of carded and crosslapped mixture of fibers. The general acoustic behavior of the composite batt structure has a low frequency absorption maximum by varying the number of crosslaps or the proportions of the fiber mixture. This allows for the composite batt structure to be tunable or layered with different laps.

Abstract: The present invention relates to an assembly wall having improved sound absorption/insulation performance and an assembly structure thereof. The assembly wall includes plate members separated from each other to face each other and each forming at least one layer; stud members alternately placed on different inner surfaces of the plate members and comprising a web formed with a plurality of first perforated holes having at least one diameter; an insulation member interposed in a space defined between the plate members and the stud members; and a sheet member adjoining an outer surface of the insulation member and being formed with a plurality of second perforated holes having at least one diameter. With this structure, the assembly wall has excellent sound absorption and insulation performance over various frequency bands including a low frequency band without increasing wall thickness.

Abstract: The invention concerns a multilayer composite material comprising at least one core (3) interposed between two external layers (1, 2), wherein: —the core (3) is a layer of thermoviscous fluid at room temperature, said thermoviscous fluid having a dynamic viscosity coefficient greater than 100 Pa·s at room temperature, —each external layer (1, 2) is in a material in the solid state at room temperature, each external layer having a surface mass of less than 8 kg/m2.

Abstract: A sound absorbent barrier has a sound absorbent layer disposed between a porous first cover and a second cover. The barrier also has a waterproof sound-permeable membrane between the first cover and the sound absorbent layer. The sound absorbent layer is thus protected from damage by the first and second covers and water ingress is prevented by the sound permeable membrane. The second cover may be non-porous to reflect sound waves which have passed through the sound absorbent layer back through the sound absorbent layer. Alternatively, the second cover may be porous to enable absorption of sound from two directions.

Abstract: An acoustic structure that includes a septum having an acoustic opening which defines an open area that varies in response to changes in the velocity of noise-containing media passing through the acoustic opening. The septum includes a fixed portion and one or more movable flapper portions wherein the fixed portion and/or the flapper portion(s) include surfaces that define an acoustic opening through the septum. The acoustic opening has an open area which varies due to movement of the movable flapper(s) in response to changes in velocity of the noise-containing media that passes through the acoustic opening. The resulting septum has a relatively low non-linearity factor (NLF).

Abstract: An acoustically absorptive panel comprises a forward airspace bounded by an acoustically transparent front fabric stretch-mounted on a support frame, and the front face of a porous acoustical absorber, the forward air space, the front fabric and the porous absorber collectively acting as acoustical absorbing chamber, wherein oppositely disposed end panels of the front fabric extend around opposing side frame members of one or more frame structures of the support frame and are connected to a pair of spaced apart retaining struts disposed between the side frame members, the distance between the retaining struts adjustable by rotating one or more threaded tension adjusters thereby stretching or relaxing the front fabric across the support frame to adjust the frequency at which sound absorption will be maximized.

Abstract: Provided is a cover member (7) such as chain cover member for engines, configured to reduce significantly its own vibrations and noises generated or transmitted therefrom compared to other conventional cover members. On its central portion, the cover member (7) of the present invention is provided with circular compartments (17) each defined by a concave surface facing outward and a convex surface facing inward. At least, the concave surfaces facing outward jointly define a continuous curved surface. Therefore, the flat surfaces (flat portions) on the cover member (7) decrease, thereby reducing sound emission, and thus noises from the cover member (7). In addition, when the cover member (7) of the present invention has at least three circular compartments (17), in each three circular compartments (17) adjoining to each other, the three circular compartments (17) are arranged in a triangular pattern, and each one of them circumscribe the other two circular compartments (17).

Abstract: A membrane is disclosed. The membrane contains a first weight disposed at a center portion of the membrane, and a first hinge structure disposed away from the center portion of the membrane.

Abstract: A sound-transmitting membrane (1) is provided that allows passage of sounds and prevents passage of foreign matters, the sound-transmitting membrane (1) including a supporting member (12) and a resin porous membrane (11) layered on the supporting member (12) and containing polytetrafluoroethylene as a main component. The supporting member (12) is a nonwoven fabric containing an elastomer. Since the supporting member (12) is a nonwoven fabric containing an elastomer, the insertion loss of the sound-transmitting membrane can be reduced for sounds of 3000 Hz.

Abstract: A wet laid basemat for an acoustical ceiling tile comprising on a dry weight basis, 50% or more mineral wool fiber, including shot, less than 9% binder, and between 5 and 20% chopped strand glass fiber, and, optionally, minor amounts of other constituents, whereby the chopped strand glass fibers serve to promote and/or maintain voids in the mat such that the dry basemat has a density of between about 7½ to about 10½ lbs. per cubic foot and an NRC substantially greater than 0.55.

Abstract: A silencer device (10) for connection to a piston compressor of a motor vehicle: a housing (11) with an inlet (12) connected to a suction line or to an air outlet of a piston compressor, and an outlet (13) connected to an air inlet of a piston compressor or to a compressed air line. A throughflow air duct (20) extends through the housing. A quarter-wave resonator (30) in the housing has an elongate resonator duct (31) which is curved in its longitudinal direction, has at one end an inlet aperture (32) situated in a wall of the throughflow duct, and has a cross-sectional area larger than or equal to that of the throughflow duct. The other end (33) of the resonator duct is closed. A motor vehicle has such a silencer device.

Abstract: A sound barrier comprises a substantially periodic array of structures disposed in a first medium having a first density, the structures being made of a second medium having a second density different from the first density, wherein one of the first and second media is a porous medium other than a porous metal, the porous medium having a porosity of at least about 0.02, and wherein the other of the first and second media is a viscoelastic or elastic medium.

Abstract: A sound insulator of the invention includes a sound absorption layer and an air-impermeable resonance layer, which are bonded to each other via an adhesive layer. The sound absorption layer has a thickness in a range of 5 to 50 mm, an area-weight of not greater than 2000 g/m2 and a two-layer structure of a high-density sound absorption layer and a low-density sound absorption layer. The high-density sound absorption layer is bonded to the air-impermeable resonance layer via the adhesive layer and has a density in a range of 0.05 to 0.20 g/cm3 and a thickness in a range of 2 to 30 mm. The low-density sound absorption layer is bonded to the other face of the high-density sound absorption layer via an adhesive layer and has a density in a range of 0.01 to 0.10 g/cm3 and a thickness in a range of 2 to 30 mm.

Abstract: A soundproofing plate comprising a substrate having a substrate having at least one through hole formed therein; and a soundproofing device mounted on the through hole of the substrate. The soundproofing device has a multiplex structure having at least a first structure and a second structure nested therein. The first structure comprises a through hole (“first air passage hole”) disposed in the center and communicating with the through hole of the substrate, and a first sound collecting portion disposed at both ends or one end and having a larger size than the aperture area of the first air passage hole, and being arranged so as to reflect incident noise. The second structure comprises a through hole (“second air passage hole”) disposed in the center and communicating with the through hole of the substrate, and a second sound collecting portion disposed at both ends or one end and having a larger size than the aperture area of the second air passage hole, and being arranged so as to reflect incident noise.

Abstract: A device with simultaneous negative effective mass density and bulk modulus has at least one tubular section and front and back membranes sealing the tubular section. The front and back membranes sealing the tubular sections seal the tubular section sufficiently to establish a sealed or restricted enclosed fluid space defined by the tubular section and the membranes, and restrict escape or intake of fluid resulting from acoustic vibrations. A pair of platelets are mounted to the membranes, with the individual platelets substantially centered on respective ones of the front and back membranes.

Abstract: A method for producing a sound-deadening insert of a silencer of an exhaust-gas discharge system in an internal-combustion engine of a vehicle; the method comprises the steps of providing a mattress made up of continuous voluminized fibers of sound-deadening material, and needling the mattress so as to cause a compacting/interweaving of the fibers in order to obtain compacting lines.

Abstract: A panel (1) including a substantially air impermeable membrane layer (3) and a layer (5) having apertures (6) therein, wherein each portion of the membrane layer (3) which overlies an aperture (6) defines a diaphragm (9) which is able to vibrate in response to sound waves incident on the membrane layer (3) and thereby absorb at least part of the sound waves' energy, at least some of the apertures (6) being arranged in clusters (11) whereby the greatest distance between adjacent apertures within a cluster (11) is less than the distance between (i) any one of the apertures (6) within the cluster (11) and (ii) any aperture (6) outside of the cluster (11), each region of the panel (1) defined by an outer periphery of a cluster (11) forming a resonance absorber (13) which is able to vibrate in response to sound waves and thereby absorb at least part of the sound waves energy, wherein at least one resonance absorber (13) is able to provide sound absorption at a frequency which is different to the frequency of reson

Abstract: It is an object of the present invention to provide an interlayer film for a laminated glass excellent in a sound-insulating property, which is preferably usable for a head up display and the like wherein a driver can look at the front view and an instrument display simultaneously without requiring to look down, and to provide a laminated glass. The present invention is directed to interlayer film for a laminated glass, which comprises at least a pair of protection layers and a sound-insulating layer sandwiched between the pair of the protection layers, and which has a wedge shape as a cross-sectional shape, a wedge angle ? of 0.1 to 0.7 mrad, the maximum thickness of 2000 ?m or thinner, and the minimum thickness of 400 ?m or thicker, the minimum thickness of the sound-insulating layer being 20 ?m or thicker.

Abstract: The assembly comprises a base spring layer made with a base of a resilient porous material, and the base spring layer being intended to be placed opposite a surface of the automobile. It comprises a stiffening layer arranged above the base spring layer and having a surface density greater than 250 g/m2 and at least one resilient porous upper layer arranged on the stiffening layer. The stiffening layer is made with a base of a dense porous material having a resistance to air flow strictly greater than 2000 N·m?3·s. The assembly advantageously has an upper resistive layer.

Abstract: A sound absorbing structure includes multiple sound absorbers. The sound absorbers are assembled together into a sound absorbing member. The sound absorbing member absorbs sound emitted from a sound source. Each of the sound absorbers is shaped like a hollow tube. Each of the sound absorbers has a hole extending in its axis direction.

Abstract: Sound barrier panels that are made from various waste materials, including scrap fiberglass reinforced plastic (FRP), scrap carpet fibers, recyclable plastics and mineral wool.

Abstract: Acoustically damped component for a vehicle, an engine, a transmission or a vehicle trim panel, includes a flat basic body provided on at least one side with a rib structure. The ribs of the rib structure form chambers which are arranged irregularly on at least one region of the component, which has a resonant frequency of from 200 to 1000 Hz. The chambers are configured irregularly in such a way that chambers of the component have different dimensioning and/or geometry in comparison with adjoining chambers, such that emitted airborne sound can be reduced and/or eradicated. A response to a transient excitation of at least two part areas of that surface of the component which is provided with the chambers having a correlation of from 0.5 to 0.85, preferably of from 0.6 to 0.7.

Abstract: A soundproofing plate comprising a substrate having a substrate having at least one through hole formed therein; and a soundproofing device mounted on the through hole of the substrate. The soundproofing device has a multiplex structure having at least a first structure and a second structure nested therein. The first structure comprises a through hole (“first air passage hole”) disposed in the center and communicating with the through hole of the substrate, and a first sound collecting portion disposed at both ends or one end and having a larger size than the aperture area of the first air passage hole, and being arranged so as to reflect incident noise. The second structure comprises a through hole (“second air passage hole”) disposed in the center and communicating with the through hole of the substrate, and a second sound collecting portion disposed at both ends or one end and having a larger size than the aperture area of the second air passage hole, and being arranged so as to reflect incident noise.

Abstract: Sound absorbing or attenuating laminate flooring materials are provided, which are directed to be used in the production of floor covering, floor panels, furniture panels, cabinets, counter-tops and wall panels. As well, the methods for producing such products are provided. In particular, abrasion resistant panels, with a laminated structure, created by forming an assembly which consists of laminating a heat-activated resin impregnated paper wear layer, a decorative layer with printed graphics or a wood veneer decorative layer, a medium density (MDF) or high-density (HDF) natural fiber-based core and a resin impregnated paper balancing layer. To achieve sound absorbing and/or attenuating properties, any or all paper layers may be pre coated with an additional flexible elastomeric coating, film or material prior to assembly of the panel, or the natural fiber core panel may be coated with a flexible elastomeric coating, film or material prior to assembly with the papers.

Abstract: A sound insulation structure for vehicles, machines and equipment powered by internal combustion engines equipped with emission control systems designed to meet the T4i and T4 emission standards is disclosed. The disclosed sound insulation structure includes a barrier core layer disposed between two insulation layers. Each insulation layer is disposed between the barrier core layer and either a facing layer or a backing layer. The insulation layers may be fabricated from fiberglass while the barrier core layer may be fabricated from a polymer or a rubberized polymer such as rubberized polyethylene. The backing and facing layers may be fabricated from non-woven materials such as non-woven cellulose fibers. The sound insulation structure may also be fire resistant.

Abstract: An acoustic protective cover assembly comprising a porous membrane and an acoustic gasket is disclosed. The porous membrane is bonded to the acoustic gasket at a peripheral region, the membrane is left unhanded at a central region. The acoustic gasket comprises a composite of a porous polytetrafluoroethylene (PTFE) polymer matrix of polymeric nodes interconnected by fibrils, resilient expandable microspheres embedded within the matrix.

Abstract: An immersion lithographic apparatus typically includes a fluid handling system. The fluid handling system generally has a two-phase fluid extraction system configured to remove a mixture of gas and liquid from a given location. Because the extraction fluid comprises two phases, the pressure in the extraction system can vary. This pressure variation can be passed through the immersion liquid and cause inaccuracy in the exposure. To reduce the pressure fluctuation in the extraction system, a buffer chamber may be used. This buffer chamber may be connected to the fluid extraction system in order to provide a volume of gas which reduces pressure fluctuation. Alternatively or additionally, a flexible wall may be provided somewhere in the fluid extraction system. The flexible wall may change shape in response to a pressure change in the fluid extraction system. By changing shape, the flexible wall can help to reduce, or eliminate, the pressure fluctuation.

Abstract: An acoustically absorptive panel comprises a porous acoustical absorber having a planar configuration mounted on a support frame, an acoustically transparent front fabric stretch-mounted on the support frame and spaced from and in parallel alignment with the front face of the porous acoustical absorber and forming an airspace, the porous absorber, front fabric and forward air space acting as acoustical absorbing chamber capable of absorbing a greater range of sound frequencies than the porous acoustical absorber alone, the range of frequencies absorbed depending on the depth of the air space.

Abstract: To provide an inexpensive, slender sound absorber, it has a plurality of porous layers or regions of different densities and different flow resistances respectively. Of significance are the boundary surfaces between the different, porous layers which are accompanied by changes in impedance. Homogenized and adapted flow resistance conditions should be avoided. Although the thermal frictional effect in the porous material is desired, in particular to absorb higher frequencies, according to the present invention it only forms one element of the absorptive working mechanism. In addition, the effect known in physics as refraction is used. At the boundary layer between two materials of different density and different flow resistance respectively there is an abrupt change in impedance. This leads to a phase shift of the sound wave, and so a sound absorbing effect is made possible.

Abstract: A panel assembly for a traffic noise barrier wall of the type including opposing slots formed in pairs of vertically-mounted posts is disclosed. In some embodiments, the panel assembly includes the following: a sheet of material having top, bottom, and side edges forming a perimeter of the sheet, the sheet having a sheet thickness that is less than each of the first slot width and the second slot width; and a frame disposed along at least a portion of the perimeter of the sheet, wherein the frame includes a bracket having a base portion with a substantially triangular cross-section, the base portion being disposed along edges of the sheet, the base portion defining a channel for capturing edges of the sheet, the channel being positioned at an apex of the base portion.

Abstract: A moldable acoustic facing comprises cellulosic fibers and synthetic fibers entangled together. The acoustic facing has a basis weight of from about 1.5 to about 5.0 ounces per square yard (osy), a thickness of less than about 0.050?, a mean pore size of between about 8 microns and about 40 microns, and an elongation at break of at least twenty percent. The acoustic facing includes less than about five percent synthetic microfiber and has an acoustic resistance of at least about 250 Rayls.

Abstract: A hearing protection process comprises (a) providing at least one hearing protection device comprising at least one sound barrier comprising at least one substantially periodic array of structures disposed in a first medium having a first density, the structures being made of a second medium having a second density different from the first density, wherein one of the first and second media is a viscoelastic medium having a speed of propagation of longitudinal sound wave and a speed of propagation of transverse sound wave, the speed of propagation of longitudinal sound wave being at least about 30 times the speed of propagation of transverse sound wave, and wherein the other of the first and second media is a viscoelastic or elastic medium; and (b) interposing the hearing protection device between an acoustic source and an acoustic receiver in the form of a human ear.

Abstract: A sound barrier membrane comprises of a decoupling layer, a barrier layer and a dampening layer. The membrane also provides crack isolation, and acts as a vapor barrier. Numerous materials are disclosed which can be used to create these layers. Methods for assembly of the sound barrier membrane are also disclosed.

Abstract: It is disclosed an anti-noise panel comprising a front shell and a rear shell that are coupled together within which rubber elements of specifically designed shape and size are incorporated. Said panel can be advantageously obtained by using also recycled, injected thermoplastic material, that allows the resulting panel to be conveniently used when the wind causes strong impact, for example, along railway lines where the compression waves generated by trains traveling at high speed over time tend to disassemble the riveted aluminum/steel sound barriers currently in use.

Abstract: A duct insulation laminate an insulation layer and a facing. The insulation layer includes an insulation layer having a first edge surface, a second edge surface that is spaced apart from the first edge surface, a first face surface that extends from the first edge surface to the second edge surface, and a second face surface that is opposed to and spaced apart from the first face surface. The second face surface extends from the first edge surface to the second edge surface. The facing is attached to the first face surface, and includes a polyester blended non-woven veil defining an outermost exterior surface of the duct insulation laminate.

Abstract: A multilayer sound absorbing structure, comprising a first microperforated film, a mesh layer and a second microperforated film disposed in this order is provided.

Abstract: A noise and vibration mitigating mat having top and bottom surfaces comprises a first layer formed of recycled bound rubber product, the first layer having a contoured bottom surface and a generally flat top surface, a second layer on the top surface of the first layer, the second layer being formed of a fabric and a third layer on the second layer and being formed of recycled rubber product.

Abstract: A method is disclosed for reducing noise and vibration within a structure of a mobile platform, wherein the noise and vibration are at least in part caused by airflow over an outer skin of the mobile platform parallel to a longitudinal line extending fore to aft along the structure. The method may involve forming the structure such that a fundamental panel vibration mode shape of the structure is not parallel to the longitudinal line.

Abstract: Acoustically damped component for a vehicle, an engine, a transmission or a vehicle trim panel, includes a flat basic body provided on at least one side with a rib structure. The ribs of the rib structure form chambers which are arranged irregularly on at least one region of the component, which has a resonant frequency of from 200 to 1000 Hz. The chambers are configured irregularly in such a way that chambers of the component have different dimensioning and/or geometry in comparison with adjoining chambers, such that emitted airborne sound can be reduced and/or eradicated. A response to a transient excitation of at least two part areas of that surface of the component which is provided with the chambers having a correlation of from 0.5 to 0.85, preferably of from 0.6 to 0.7.