Abstract: A musical instrument includes: an acoustic portion that makes sound in response to vibration; an exciter that includes an exciter body and a vibrating portion vibrating with respect to the exciter body, and excites the acoustic portion; and a support portion that is attached to the acoustic portion and supports the exciter body such that the vibration is transmitted from the vibrating portion to the acoustic portion. The support portion supports the exciter body such that the exciter body is elastically displaced with respect to the acoustic portion. A resonance frequency of a vibration system including the exciter body and the support portion is lower than the lowest resonance frequency of the acoustic portion.

Abstract: The disclosure provides a wireless communication device, an electronic device, and a wireless communication method. A wireless communication device is connected to an electronic musical instrument and transmits and receives MIDI data input to and output from the electronic musical instrument to and from other wireless communication devices paired through wireless communication at a predetermined communication interval, the pair is formed with each of a plurality of the other wireless communication devices. The wireless communication device includes a communication interval setting part configured to set a communication interval of each pair to a different time interval; and a communication interval transmission part configured to transmit the communication intervals set by the communication interval setting part to the corresponding other wireless communication devices.

Abstract: In some embodiments, a dielectric elastomer device may include at least first and second dielectric elastomer layers, and a first layer of conductive particles disposed between the first and second dielectric elastomer layers and forming a first electrode of the device, wherein portions of the second dielectric elastomer layer are directly bonded with portions of the first dielectric elastomer layer through the first layer of the conductive particles. The dielectric elastomer layer may, for example, comprise a cured acrylic elastomer precursor with an additive including urethane, polybutadiene, or silicone. Electrodes in different layers may be interconnected by infusing a liquid or semi-liquid conductive material in contact with each of a plurality of the electrodes of the actuator or sensor device, and solidifying the conductive material to form a conductive path that interconnects the plurality of electrodes.

Abstract: A resonator insert (14) is provided for coaxial and sectionally radially spaced insertion in an intake pipe of a turbocharger (10). The resonator insert (14) has a tube section (141) with a wall having circumferentially extending, axially adjacent through-slots (142). The wall of the tube section (141) carries at least one radially outwardly directed, axially extending lamella (144) crossing the through-slots (142). A turbocharger with an upstream resonator also is provided.

Abstract: A freestanding booth comprising upstanding peripheral walls, a roof and a base upon which the booth stands in use, one of the walls defining an opening that is closed by a door, wherein the base extends along a basal edge of a first of the walls, the first wall being fixed to the base via a first levelling assembly, the first levelling assembly comprising a first height adjustment mechanism and a second height adjustment mechanism that are spaced apart from one another in a longitudinal direction of the basal edge of the first wall and are independently adjustable for altering an angle of the basal edge of the first wall relative to the ground.

Abstract: Provided is a speaker box, including a housing having receiving space, a sounding unit received in the housing, and a solder terminal electrically connecting the sounding unit to an external circuit. The housing includes a plastic member and a reinforced rigid body fixed to the plastic member by injection molding. The plastic member includes a bottom wall connected to the reinforced rigid body, a blocking wall connected to the bottom wall, and an enclosure extending from the bottom wall away from the reinforced rigid body. The solder terminal includes a main body portion, first and second electrical connection portions. The enclosure is separated from the blocking wall by a distance and encloses the main body portion. The enclosure and the reinforced rigid body are bonded by glue. The speaker box has low costs, simple assembly and high assembly stability.

Abstract: A soundproofing coating with a cellular structure having several structures connected in a transverse direction, each formed by connecting a first longitudinal strip with a second longitudinal strip. Each structure has, successively in the longitudinal direction, 1) a first cavity, the cross-section of which narrows gradually in the thickness of the coating until it closes, 2) a first connection of two walls, respectively of the first strip and the second strip, in contact with each other over part of the thickness of the coating, which provides a passage between the first cavity and a second cavity that thus form a Helmholtz resonator, 3) the second cavity, the cross-section of which gradually increases in the thickness of the coating and which is closed by a closing sheet, and 4) a second connection of two walls.

Abstract: A switch lock apparatus for a guitar having a pickup selector switch is disclosed herein for locking a position of the pickup selector switch. The switch lock apparatus may include a body plate, a mounting hole, a switch opening defined in the body plate which is configured to receive the pickup selector switch. The switch lock apparatus may also include at least one first side receptacle positioned along the first switch opening side and at least one second side receptable positioned along the second switch opening side. The at least one second side receptacle may be offset from the at least one first side receptacle along the switch opening length to define a central passageway that enables free movement of the pickup selector switch. The switch lock apparatus may define a locked position when the pickup selector switch is received by one of the first or second side receptacles.

Abstract: In a soundproof structure body including a tubular tube body having an opening portion, and a resonance type soundproof structure, in which a phase difference ?, at an upstream of the resonance type soundproof structure, between a reflected wave in the resonance type soundproof structure and a reflected wave of a transmitted wave transmitted through the resonance type soundproof structure and reflected by the opening portion satisfies Inequation |???|??/3 with respect to a resonance frequency of the resonance type soundproof structure. This soundproof structure body can effectively offset a reflected wave from a resonance type soundproof structure body by opening end reflection by appropriately specifying positions of the resonance type soundproof structure and the opening end portion of a duct, a tube line, or the like to improve an absorbance of a single resonance type soundproof structure.

Abstract: A speaker grill includes a diffusion plate, a base, and a support portion. The diffusion plate forms an opening facing in a sound-emitting direction of a speaker and that is arranged on an outer side of the opening. The base supports the diffusion plate at an outer circumference thereof. The support portion is provided at a front surface of the diffusion plate in the sound-emitting direction, having a support surface that covers at least a portion of the front surface of the diffusion plate, and having a plurality of partition walls forming slits in the sound-emitting direction. The support surface forms a virtual surface covers an outer surface of the base.

Abstract: A resistive skin shell for an acoustic panel or inner wall of an aircraft air intake, comprising an alternation, in a transverse direction, of perforated metal bands and of composite solid bands extending in a longitudinal direction. The perforated metal bands and the composite solid bands form a smooth outer face configured to be in contact with an aerodynamic stream, and a crenelated inner face. The composite solid bands have a thickness greater than the perforated metal bands. Since the perforations are provided in metal bands, which are intrinsically resistant to wear and erosion, the future proofing of the acoustic performance of the resistive skin is guaranteed. Since the composite solid bands, which are thicker, can ensure the mechanical strength of the skin, the thickness of the perforated metal bands can be reduced, allowing perforations with dimensions that are also reduced, having a lower impact on drag.

Abstract: An ultrasonic vibration device has a sonotrode and a converter, the converter having a piezoelectric actuator for converting an electrical alternating voltage into a mechanical vibration. A first piezoelectric sensor element outputs a first measurement signal which varies in dependence on the vibration amplitude of the mechanical vibration. To permit measurement of at least one intensive state variable like the temperature, or the aging state of the piezoelectric actuator, a second piezoelectric sensor element outputs a second measurement signal which also varies in dependence on the vibration amplitude of the mechanical vibration. However, the second piezoelectric sensor element differs in a physical property from the first.

Abstract: Compressor head fixing device, a compressor and a refrigeration device. The compressor head fixing device includes a cylinder block and a cylinder head cover, the cylinder head cover being connected to the cylinder block by a fastener, the cylinder block being provided with a compression chamber and an assembly hole configured to fix the fastener; a noise reduction chamber, provided on the cylinder block; and a communication passage, provided in the cylinder block and the cylinder head cover, and being in communication with the assembly hole, the noise reduction chamber and the compression chamber. The compressor head fixing device has a compact structure, a length of the exhaust passage is shortened and the exhaust pressure is reduced.

Abstract: A serrated stethoscope tube is disclosed herein. The serrated stethoscope tube includes a tubular body portion, the tubular body portion having an exterior surface and an interior surface, the interior surface being oppositely disposed relative to the exterior surface, and the interior surface of the tubular body portion having a plurality of channels formed therein for reducing sound wave refraction and/or reverberation.

Abstract: A suppressor for firearms, comprising: a casing, comprising; a first end cap, an elongated hollow member, and an second end cap, an upstream disk secured in place between the first end cap and the elongated hollow member; a first hollow diffuser tube having a first end and a second end and a plurality of openings distal to the first end; a second hollow diffuser tube having a first end and a second end and a plurality of openings distal to the first end; and a downstream disk, wherein the disk has a centric opening.

Abstract: A stethoscope and binaural assembly are disclosed herein. The stethoscope includes a stethoscope chestpiece assembly and a binaural assembly including a first ear tube, a second ear tube, and an acoustic tube connected to the first and second ear tubes, the first ear tube being flexibly connected to the second ear tube by at least one spring member disposed inside the acoustic tube, a portion of the at least one spring member being located proximate to a sound transmission junction of the acoustic tube, the binaural assembly further including a junction blockage prevention member, the junction blockage prevention member configured to prevent one or more internal sound passageways of the sound transmission junction of the acoustic tube from becoming blocked or partially blocked by the at least one spring member when the first and second ear tubes are flexed outwardly away from one another by a user.

Abstract: An acoustic filter suitable for an electro-acoustic transducer includes a relatively high frequency driver and a relatively low frequency driver situated on a common axis. The acoustic filter includes a baffle body having an outer side and an inner side, such that the outer side serves as a baffle for the high frequency driver. The inner side forms a first wall of a Helmholtz resonator including a chamber and a vent duct communicating with the chamber.

Abstract: A method for controlling an electronic device with a remote control includes detecting a motion of the remote control and determining a command associated with the detected motion. The determined command is sent from the remote control to the electronic device. A corresponding remote control includes a motion detector for detecting a motion of the remote control, a device for determining a command associated with the detected motion, and a transmitter for sending the determined command to the electronic device.

Abstract: A correlated color temperature (CCT) of one or more luminaires is controlled by obtaining a target CCT for the one or more luminaires and obtaining a first profile associated with a first luminaire of the one or more luminaires. A first target power for a first direct-current (DC) power input of the first luminaire and a second target power for a second DC power input of the first luminaire are calculated based on the target CCT and the first profile so that the first target power and the second target power drive the first luminaire to emit light at the target CCT. A first DC power supply is controlled to deliver the first target power to the first DC power input of the first luminaire and a second DC power supply is controlled to deliver the second target power to the second DC power input of the first luminaire.

Abstract: The invention is directed to an operation-control node (100) for controlling operation of one or more external lighting devices (101, 103) via a local-area wireless communication network. The operation-control node is configured to receive from a user-input device (105) input signals (I) indicative of respective operation-control data forming a list of settings of a control parameter values of a lighting control parameter for sequentially controlling operation of a lighting device.