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: The present invention relates to a sound converter, and, more particularly, to a sound converter which can solve a problem in that a vibration space decreases in the sound converter requiring high outputs, as the overall height of a voice coil increases.

Abstract: The present disclosure relates to a diaphragm that may be used with a mechanical-to-acoustical transducer. The diaphragm may include a layer of optically clear film, a damping layer and another layer of optically clear film. The damping layer may be an adhesive. The diaphragm may also comprise two optically clear films, optionally including a damping layer, wherein the films indicate a desired coefficient of linear thermal expansion in one or both of the machine and transverse directions.

Abstract: An adjustment assembly for snare wires includes an adjustment unit and a pressing unit respectively located on two opposite positions of the shell of a snare drum. The adjustment unit has a body with a slide slot. A shifting member is slidably connected to the body and driven by a driving member connected to the body. The shifting member has a wire carrier which is adjusted by rotating an adjusting bolt. The pressing unit includes another wire carrier which is controlled by another adjusting bolt. By adjustment of the two adjustment bolts, the tension of the snare wires can be adjusted.

Abstract: An assembly is configured to provide insulation and sound-dampening within an air-handling system. The assembly includes a single housing defining an internal chamber, at least one sound-absorption member within the internal chamber, wherein the at least one sound-absorption member is configured to dampen sounds generated by or within the air handling system, and an insulative material within the internal chamber, wherein the insulative material is configured to insulate the air handling system.

Abstract: A method and apparatus comprising a composite panel and a number of structures to reduce noise radiation from the composite panel. The composite panel has a first face sheet, a second face sheet, and a core located between the first face sheet and the second face sheet. The number of structures is associated with the first face sheet. The number of structures has a mass with a configuration to reduce a speed of waves propagating in the composite panel such that noise radiating from the composite panel is reduced.

Abstract: A musical drum support stand which supports a musical drum and suspends it off the ground or floor surface. The support stand includes a base section that defines an opening and a first member typically ring-shaped and a spaced-apart second member also typically ring-shaped situated below the first member. A plurality of spaced-apart brace support members are provided to join the first member to the second member with each of the brace support members being alternatively curved in concave-convex relation and adapted for detachably receiving and securely gripping the drum shell's base section and holding it in suspension off the ground.

Abstract: The invention relates to a sound insulating element for the ceiling area of a building, in particular for rooms subject to increased humidity such as underground parking, and basement rooms, which sound insulating element consists of an insulation element (2) made from mineral fibers bound with a binding agent and having two mutually spaced large surfaces extending parallel to each other, and of a coating (5) from a hydraulically and/or chemically set mass, wherein the coating (5) is connected to the insulation element (2), whereby the coating (5) to be oriented towards the room includes an array of openings (7) forming a regular hole pattern and penetrating the coating (5) as far as to the insulation element (2). The invention moreover relates to a process for producing said sound insulating element.

Abstract: A noise attenuator which can reduce time and cost for installation thereof as compared with the conventional configuration and a vehicle air intake duct provided with the noise attenuator are provided. The noise attenuator includes a pair of circular through holes formed through a duct wall, a pair of wave transmitting/receiving membrane which are stretched so as to close the circular through holes, and a seesaw member which connects between central portions of the paired transmitting/receiving membranes. Accordingly, when one of the membranes receives a sound wave of noise thereby to be vibrated at a predetermined frequency, the other membrane follows it and is also vibrated while shifted by a half cycle. As a result, a cancellation wave with a phase opposite to the sound wave received by the one membrane is transmitted from the other membrane, whereupon the noise can be attenuated.

Abstract: Sound chests having a sound board connected to a hollow body which includes a bearing structure to which there is connected an outer shell are provided. In such sound chests the bearing structure includes a bottom wall or chest-bottom, and a top member or upper block, a central longitudinal batten or backboard, and two side battens or planks, which extend between the chest-bottom and the upper block, remote from and close to the sound board, respectively; and a plurality of longitudinally staggered, transverse stiffening members or bridges each of which is connected centrally to the backboard with its ends connected to the side planks. Methods for making such sound chests are also provided.

Abstract: A speaker device for a mobile terminal enlarges resonance space of a speaker while decreasing a size of the mobile terminal. The speaker device for a mobile terminal includes at least one speaker installed within a main body of the mobile terminal and a speaker bracket installed at one surface of an electronic circuit board mounted within the main body. In addition, the speaker bracket fixes the at least one speaker in place and has housing space to enclose the at least one speaker therein. At least one resonance groove is formed in a portion enclosed by the speaker bracket in one surface of the electronic circuit board. Because resonance space can be enlarged without increasing a size of the speaker bracket, an entire thickness of the mobile terminal can be reduced and thus a size and thickness of the mobile terminal can be decreased.

Abstract: An exhaust device of an engine includes an exhaust pipe connected to the engine, a silencer connected to the exhaust pipe and structured of an outer cylinder and an inner cylinder in which plural holes are formed, and a sound absorbing material disposed in a space formed between the inner cylinder and the outer cylinder. The exhaust device further includes a partition wall partitioning the space and supporting the sound absorbing material so that the sound absorbing material does not move in an axial direction of the silencer, and the partition wall includes a continuous hole allowing exhaust gas to flow through an upstream side to a downstream side of the partition wall in the space.

Abstract: An acoustic material can be electromagnetically tuned to produce alterations in its acoustical properties without physical contact. The acoustic material should contain a periodic structure and a medium that has acousto-elastical properties that can be altered through the application of electromagnetic radiation. Changes in volumetric properties such as density result in changes to the velocity at which sound passes through the material. The acoustic material can be a phononic crystal that undergoes a change in its acoustic bandgap after being subjected to electromagnetic radiation. This electromagnetic tuning ability results in the ability to change the acoustic properties of various phononic devices without physical contact.

Abstract: The present invention relates to a housing (1) with a jacket (2), enclosing a housing interior space (7) in circumferential direction (8). For reducing self-induced vibrations of the jacket (2), at least one preloading device (14) is proposed, which is arranged in the housing interior space (7), which supports itself on a first supporting region (15) of the jacket (2) on the inside of the jacket (2) subject to a first preload (16) orientated towards the outside and which supports itself on a second supporting region (17) of the jacket (2) spaced from the first supporting region (15) on the jacket (2) on the inside subject to a second preload (18) orientated towards the outside.

Abstract: Sound-damping housing for a pump and for a drive motor for said pump, comprising a block-like casing assembled from sound-damping panels and provided with a support construction and a first door opening for successively placing into and removing from the casing the pump and its drive motor on the support construction, and with at least one guide extending over the support construction transversely of the door opening for the purpose of guiding a pump and its drive motor to be placed in the casing.

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: Exemplary embodiments are directed to a cooling apparatus for cooling a power electronic device, the apparatus including at least one panel that is adapted to be thermally connected to a heat source in order to receive heat from the heat source. The panel is also adapted to be thermally in contact with an air flow in order to transfer heat from the panel. The panel includes at least one hole between a first side of the panel and a second side of the panel. The hole is adapted to attenuate a vibrating air pressure generated by an acoustic noise source and carried by the air.

Abstract: A muffler of a motorcycle having an outside diameter greater than the outside diameter d1 of a rectilinear portion of a branch pipe is disposed at a transverse portion of an exhaust pipe. Since the muffler is formed to be roughly elliptic in sectional shape, the outside diameter of the muffler is represented by a major diameter da as the length in the direction of a major axis and a major diameter db as the length in the direction of a minor axis. When the muffler is disposed between a swing arm and a seat to be along the transverse portion of the exhaust pipe, the muffler can be disposed on the more vehicle front side while securing the capacity thereof. Therefore, protrusion of the muffler toward the rear of the vehicle is suppressed, and the external appearance of a vehicle rear portion is enhanced.

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: A resonator is provided, having an adaptable resonator frequency for absorbing sound generated by a gas stream of a gas turbine. The resonator includes a neck section, a chamber and a deformable element being deformable under influence of a change of a gas turbine temperature of the gas stream. The shape of the deformable element is predetermined with respect to a respective gas turbine temperature. The neck section and the chamber form a volume of the resonator. The neck section forms a passage coupling the volume with the gas turbine. The deformable element is thermally coupled to the gas turbine in such a way that the shape of the deformable element depends on the respective gas turbine temperature. The deformable element forms a spiral and is installed to the neck section in such a way that an effective diameter of the neck section depends on the gas turbine temperature.