Abstract: A sensory signal output apparatus is provided. The sensory signal output apparatus, includes: a magnetic circuit vibrating in response to an alternating signal flowing through a coil; and an elastic support means elastically supporting the magnetic circuit to surround the circumferential outer surface of the magnetic circuit from one side direction thereof, in which coupling recesses are formed at the circumferential outer surface of the magnetic circuit to be spaced apart from each other, and a coupling piece is provided at a periphery of the elastic support means to be coupled to the coupling recess, the coupling piece is attached to and inserted into the coupling recess. In the sensory signal output apparatus, an elastic support means is inserted into and coupled to a magnetic circuit without using a curling operation to provide easy coupling.

Abstract: A loudspeaker driver that includes a suspended diaphragm and at least one voice coil disposed lateral to the suspended diaphragm, suspended in a magnetic field and coupled to the diaphragm.

Abstract: An electronic device is provided. The electronic device includes a housing and an electro-acoustic transducer disposed on the inner surface of the housing. The electro-acoustic transducer includes an electret diaphragm, a conductive plate and at least one spacer. The electret diaphragm is positioned on the inner surface of the housing and has a film body and an electrode layer. The film body has static charges and the electrode layer is formed on the lower surface of the film body. The conductive plate has a plurality of openings and is stacked on the upper surface of the film body. The spacer is positioned between the electret diaphragm and the conductive plate to keep a predetermined distance therebetween.

Abstract: A loudspeaker having a magnet system and a method of assembling the magnet system are disclosed. The magnet system comprises a magnet and an armature core that is mounted on the magnet. The magnet system also includes a shell pot configured to receive the magnet and the armature core in a hollow interior. The magnet system further includes a shaft that interlocks with the magnet, the armature core and the shell pot, and that is, on one end, mechanically connected to the shell pot. The magnet system also includes a push-on fastener that has an aperture through which the shaft passes and that is secured to the shaft at another end of the shaft such that it applies pressure onto the first surface of the armature core to fixedly position the armature core and the magnet with respect to the shell pot.

Abstract: Acoustic loudspeaker comprising: a movable membrane; a source of constant magnetic field, a coil mechanically secured to said membrane and interacting with the magnetic field so as to displace the membrane, when it is traversed by an alternating current, characterized in that the membrane carries the coil at its periphery, and in that the magnetic field source is formed by a set of at least one magnetized element disposed at the periphery of said membrane, around the coil, the magnetic field generated by said at least one magnetized element being in a plane parallel to the membrane.

Abstract: A proximity sensor for use in a portable computing device is described. In particular various embodiments of a proximity sensor which fit in an extremely small portion of a cellular phone, and accurately determine the presence of a user's head in close proximity to a surface of the cellular phone.

Abstract: An electroacoustic transducer includes a frame defining a hollow space, and an elastic member mounted on the frame. The elastic member includes a circular plane lamina and a plurality of elastic arms extending outwardly from a circumference of the circular plane lamina. A diaphragm includes a vibrating film mounted with the circular plane lamina, and an edge damper integrally formed with an outer periphery of the vibrating film. A voice coil is attached below the vibrating film and electrically connected to the circular plane lamina. At least two through holes are formed between an outer periphery of the circular plane lamina and an inner side of the voice coil for balancing the air pressure of the air below the diaphragm.

Abstract: The present invention provides a sensory signal output apparatus wherein a coil is disposed in the gap between a magnet/top plate and a yoke, and a portion elastically supported in the free space vibrates in reaction to the magnetic flux generated in the gap in accordance with the direction of the alternating current signal applied to the coil to generate sound and/or vibration, wherein the yoke has a groove formed at a side other than that with the magnet, and the groove has a diameter smaller than that of the magnet, and an inner edge portion with a magnetic fluid. The sensory signal output apparatus of the present invention improves the position retaining force of the magnetic fluid and reduces the deformation of the magnetic fluid, as the magnetic fluid is formed in the edge of the groove of the yoke corresponding to the edge portion of the magnet which has a relatively bigger magnetic force and magnetic field than the plane portion of the magnet.

Abstract: An electro-acoustical transducer comprising DC atmospheric pressure equalization vents for equalizing pressure in both chambers therein. The sound port of the transducer may be sealed by a sound conducting member preventing gas flow there through. The transducer may have a single vent extending in a plane of a side portion, which vent may have a meandering path or may comprise tapering portions or cavities defining acoustical properties thereof.

Abstract: A speaker apparatus in accordance with the present invention is for use with a vehicle having a compartment and is to be mounted to the vehicle. The speaker apparatus includes: an interior member including a hole edge that defines an attachment hole; a speaker unit configured to be placed in the attachment hole, the speaker unit including a limiting member; and a speaker grille configured to be attached in the attachment hole from an inside of the compartment, the speaker grille including a claw-fixing portion that is bendable and is configured to be engaged with the hole edge. Accompanying the engagement of the claw-fixing portion with the hole edge, the speaker grille is fixed to the interior member. Accompanying the placement of the speaker unit in the attachment hole, the limiting member is positioned in a bending space for the claw-fixing portion and thereby prevents disengagement of the claw-fixing portion from the hole edge.

Abstract: A microelectromechanical system microphone package structure includes a base plate and a plurality of chips is provided. The plurality of chips are disposed on the base plate, wherein an active area of each of the chips is disposed with a microelectromechanical system microphone structure, each of the active areas comprises a normal line, and the normal lines of the chips are unparallel and nonorthogonal to each other.

Abstract: The invention is a novel circuit wherein maximum shove is achieved yet the transducer's height profile is minimized. The profile is minimized by using mated beveled surfaces on an annular magnet and the top plate which prevents the top plate from reaching saturation and reduces the reluctance f the magnetic flux path. A novel anti-fringe geometry to reduce flux leakage and net saturation in the center post improves the magnetic reluctance of the circuit. An external housing assembly is provided with integral suspension elements for radial stiffness and axial compliance and for aligning the circuit within the housing to prevent cocking and resulting distortion.

Abstract: A method of protecting a resonating sensor is described. The protected resonating sensor may include at least one passive ultrasonically excitable resonating sensor unit. Each sensor unit has one or more vibratable members having a resonating frequency that varies as a function of a physical variable in a measurement environment. The sensor is protected by forming one or more protective chambers defined between a compliant member and the vibratable member(s). A substantially non-compressible medium is disposed within the protective chamber(s). The compliant member has a first side that may be exposed to a measurement environment and a second side that may be exposed to the substantially non-compressible medium. The substantially non-compressible medium may be a liquid or gel and is in contact with the vibratable member(s). When the medium is a liquid, the chamber is sealed. When the medium is a gel, the chamber may be sealed or non-sealed.

Abstract: A low profile miniature speaker configured for use in greeting cards such as sound generating greeting cards and other novelties. The thickness of the speaker is minimized while maintaining the sound quality and increasing strength. The speaker magnet is counter-sunk into the housing of the speaker, thereby decreasing overall thickness. The speaker is configured with concentric ribs that radiate outward from the center of the circular speaker. The ribs reinforce the plastic housing and increase the structural strength of the speaker.

Abstract: A damper, which is an element of a speaker and suppresses the rolling of a voice coil unit, includes a corrugated structure portion at its inner periphery and a leaf spring at its outer periphery. By coupling the corrugated structure portion to the voice coil unit and coupling the leaf spring to the frame, the distortion of a speaker can be reduced and the driving efficiency can be improved.

Abstract: A spring plate includes an engaging portion, a connecting portion, a first elastic portion, a second elastic portion, a first fixing portion, and a second fixing portion. The first elastic portion and the second elastic portion are connected to the engaging portion and the connecting portion, the first fixing portion and the second fixing portion are formed on opposite ends of the connecting portion. The engaging portion defines a recess. The present disclosure further provides a voice coil motor using the spring plate.

Abstract: A multi-functional subminiature speaker, namely a bone conduction speaker, which can generate vibration for a bone conduction function, bodily sensation of vibration, speaker attachment, and the vibration modes over the housing unit, without any projections, and which has an acoustic portion unit detachably mounted. The bone conduction is performed without the projections because the vibration can be generated over the whole surface of the multi-functional subminiature speaker, such that loss of the magnetic force transmitted to the vibration coil is minimized by disposing the magnets on both inner and outer sides with respect to the vibration coil.

Abstract: A loudspeaker driver has a diaphragm connected to a surrounding frame by a roll suspension which extends around the diaphragm and within the frame. The roll suspension connects the outer edge of the diaphragm to the inner edge of the frame and flexes as the diaphragm is displaced to and fro axially relative to the frame. In order to provide for better integrity of the roll suspension during its displacement, and reduce unwanted deformation and concomitant distortion, the suspension roll is provided with pleats extending across the roll suspension transversely to the direction of axial movement of the diaphragm to create a series of undulations (peaks and troughs) around the perimeter of the roll suspension. In transverse cross-section, the roll suspension is parabolic. The roll suspension varies continuously between each peak and adjacent trough.

Abstract: A speaker assembly, a method for manufacturing a speaker assembly and a wireless device are provided. Such a speaker assembly may include a diaphragm for generating sound, a transducer for causing the diaphragm to generate sound and an integrated inductive element that is electrically connected to the transducer. The diaphragm, transducer and integrated inductive element are contained within the speaker assembly.

Abstract: A vibration device includes a support system member that supports a diaphragm to allow vibration, a tubular voice coil bobbin attached to the diaphragm, and a magnet disposed on at least one of inner and outer circumferential surface sides of the bobbin. The magnet is polarized in a vibration direction of the diaphragm, and forms a magnetic gap on a side that faces the bobbin. A voice coil is attached to the bobbin and disposed within the magnetic gap, and vibrates the diaphragm and the bobbin in response to a driving force generated when an electrical signal is inputted into the voice coil. A magnetic material member is attached to the bobbin, disposed in a balancing position within the magnetic gap, and, when vibrating with the bobbin, subjected to a magnetic attractive force in a direction away from the balancing position.

Abstract: A low cost sound recording and playback device and a low cost method for wirelessly communicating with, and recharging of, the device. The device utilizes commonly available electronic components generally included in electronic sound producing devices thereby allowing for lowest cost of manufacture. The device includes a low cost low-power processor, general purpose low-cost loudspeaker, and a power source. The method incorporates inductive coupling between an external communication and recharging device, and the internal loudspeakers voice coil of the device. Substantial reductions in cost and space savings are realized by utilizing the internal loudspeaker's voice coil for multiple purposes.

Abstract: A computer implemented method employing experience transfer to improve the efficiencies of an exemplary configuration tuning in computing systems. The method employs a Bayesian network guided tuning algorithm to discover the optimal configuration setting. After the tuning has been completed, a Bayesian network is obtained that records the parameter dependencies in the original system. Such parameter dependency knowledge has been successfully embedded to accelerate the configuration searches in other systems. Experimental results have demonstrated that with the help of transferred experiences we can achieve significant time savings for the configuration tuning task.

Abstract: A miniature receiver or transducer with improved viscous damping. The receiver may be a moving armature receiver using shearing forces for damping the deflection of the diaphragm. In this receiver, the damping element, which may be a liquid, extend in a direction of the deflection of the armature or diaphragm. Another embodiment relates to a transducer where the damping element engages the diaphragm.

Abstract: A vibration diaphragm for a speaker has a spherical bowl section, an annular intervening section and an annular outer section. The spherical bowl section has a top and a spherical cavity defined in the top. The annular intervening section is formed on and protrudes radially outward from the spherical bowl section. A bending line is formed on a boundary between the spherical bowl section and the annular intervening section. An annular outer section is formed on and protrudes radially from the annular intervening section and extends obliquely outward in a direction along which the cavity is sunk, wherein a bending line is formed on a boundary between the annular intervening section and the annular outer section, and an obtuse angle is defined between the annular intervening section and annular outer section.

Abstract: A sandwich-type woofer with two sound wave propagation directions includes a first magnetic-conducting plate unit, a second magnetic-conducting plate unit, a magnet unit, a coil frame, a first vibrating unit, a second vibrating unit, a first coil and a second coil. The magnet unit is sandwiched between the first and second magnetic-conducting plate units. The coil frame extends through the first and second magnetic-conducting plate units and the magnet unit, and has first and second ends. The first vibrating unit is disposed at the first end of the coil frame and the second vibrating unit is disposed at the second end of the coil frame. The first coil is arranged on a portion of the coil frame corresponding to the first magnetic-conducting plate unit and the second coil is arranged on another portion of the coil frame corresponding to the second magnetic-conducting plate unit.

Abstract: A low profile miniature speaker configured for use in greeting cards such as sound generating greeting cards and other novelties. The thickness of the speaker is minimized while maintaining the sound quality and increasing strength. The speaker magnet is counter-sunk into the housing of the speaker, thereby decreasing overall thickness. The speaker is configured with concentric ribs that radiate outward from the center of the circular speaker. The ribs reinforce the plastic housing and increase the structural strength of the speaker.

Abstract: A loudspeaker magnet assembly for a loudspeaker transducer having a voice coil is provided that has a low profile construction. The loudspeaker magnet assembly may include: a first magnet assembly; top plate position below the first magnet assembly; second magnet assembly positioned below the top plate; and bottom plate positioned below the second magnet assembly. The first magnet assembly may include an annular outer magnet and a circular inner magnet. The top plate may include an annular outer top plate and a circular inner top plate and the second magnet assembly may include an annular outer magnet and a circular inner magnet.

Abstract: A transducer magnet for a low profile loudspeaker transducer is provided having a voice coil, surround suspension, diaphragm, and top plate. The transducer magnet may include a first magnet assembly, including an annular outer magnet having an outer perimeter, an outer diameter and an inner diameter. The inner diameter defines a vacant circular center within the annular outer magnet, and the difference in length between the diameter of the circular inner magnet and the inner diameter of annular outer magnet define an annular first magnet assembly air gap. The annular outer magnet includes one or more channels extending inwardly from the outer perimeter of the annular outer magnet to the first magnet assembly air gap, which is configured to receive the voice coil. The channels are configured to pass hookup wires from the voice coil to an external device from the transducer magnet.

Abstract: A speaker device includes a pair of diaphragms disposed opposite each other, a frame configured to vibratably support an outer periphery of the diaphragms in a vibration direction, and a plurality of driving parts configured to support a rear surface of each of the diaphragms and vibrate the diaphragms in response to an audio signal. The plurality of the driving parts include a pair of magnetic circuits in which a magnetic gap is formed in a direction different from the vibration direction of the diaphragms, a pair of voice coils vibratably arranged in the magnetic gap in one axis direction, vibrating so as to move toward or away from each other in response to the audio signal, and a rigid vibration direction converter part direction-converting the vibration of the voice coils and transmitting the vibration to the diaphragms.

Abstract: The invention provides a speaker in which a damper is effectively added without impairing the thinness of the speaker, and which, although the speaker is thin and small, exhibits high withstand input and high output power performances. A damper (14) is disposed between the lower end of a voice coil bobbin (12) and a magnet (3) of a magnetic circuit (5), and supports a vibration system (13) in a manner that the system is vibratable with respect to the magnet (3).

Abstract: An electronic device having an enclosure including an upper panel and a bottom panel operably connected to the upper panel. A transducer is operably connected to the enclosure and the transducer is configured to mechanically vibrate the enclosure. The transducer includes a magnet, an electromagnetic coil and a retention element maintaining a relationship between the magnet and the electromagnetic coil.

Abstract: Improved loudspeakers, systems and components are adapted to interconnect with many forms of communication media. In one embodiment, a speaker is mountable within a receptacle. The speaker includes a magnetic driver and a diaphragm mounted to a frame. The frame includes a mounting member extending from a surface of the frame behind the flange plane. The mounting member is engagable in a notch formed in the receptacle for securing the speaker within the receptacle. In another embodiment, a low-profile loudspeaker has a front-mounted magnetic driver disposed within a cone-shaped acoustic diaphragm. The magnetic driver includes a first rare earth magnet centrally disposed within an electromagnetic shielding material. In another embodiment, a low-profile, two-way loudspeaker includes a cone-shaped diaphragm and a dome-shaped (tweeter) diaphragm. A front-mounted magnetic driver comprises first and second rare earth magnets each centrally disposed within electromagnetic shielding material.

Abstract: An electronic device includes a jack electrically connecting an outer speaker, a power controller, an audio generator electrically connecting the jack and the power controller, and an inner speaker. The inner speaker includes a housing, a magnet, a vibrating element, and a first electromagnetic inducting coil. The magnet and the vibrating element are configured in the housing. The vibrating element electrically connects the audio generator via the jack to be vibrated relatively to the magnet for sounding. The first electromagnetic inducting coil is configured on the vibrating element and electrically connected to the power controller to generate electricity induced by a magnetic field of the magnet. A power storage is charged by the electricity via the power controller. Through the jack and the power controller, the power storage is charged by electricity generated by a second electromagnetic inducting coil of the outer speaker.

Abstract: An apparatus (100) including two housings and a piezoelectric transducer is disclosed. The apparatus may include a first housing (110), a hinge (115) coupled to the first housing, and a second housing (140) coupled the first housing via the hinge. The first housing can have a closed position when the first housing is substantially adjacent to the second housing and the first housing can have an open position when a portion of the first housing is substantially away from the second housing. The apparatus can also include a first piezoelectric element (130) coupled to the second housing where the first piezoelectric element can be substantially in contact with the first housing when the first housing is in the closed position. The apparatus can further include a user interface (140) coupled to the second housing and a controller (150) coupled to the first piezoelectric element and the user interface.

Abstract: An acoustic mirror of alternately arranged layers of high and low acoustic impedances is manufactured in that a basic material having a first layer of the layer sequence is initially provided, on which a second layer of the layer sequence is created on the first layer such that the second layer of the layer sequence partially covers the first layer. Subsequently, a planarization layer is applied onto the layer sequence, and the planarization layer is removed in an area which in the common layer plane projects laterally beyond the second layer so as to result in a residual planarization layer. Finally, a termination layer is applied onto the layer sequence and the residual planarization layer.

Abstract: A slender-type diaphragm longer in a longitudinal direction and shorter in a transversal direction in relation to the longitudinal direction, has a base member and a slant member. The base member has a pair of extending members provided in parallel in the longitudinal direction as facing each other, and a curved section that protrudes toward a first side of the diaphragm in a vibration direction of the diaphragm from a first plane that includes the extending members, the vibration direction being perpendicular to the longitudinal and transversal directions. The slant member has a slant surface in relation to the first plane and connected to the base member in a manner that the slant member surrounds the base member in a second plane parallel to the first plane, the slant member having a curved surface in a cross section thereof in relation to a cross section of the base member in the transversal direction.

Abstract: A speaker apparatus includes an acoustic vibration plate, and an actuator mounted to the acoustic vibration plate such that one end and the other end thereof, in a driving axis direction, exist in a plate surface of the acoustic vibration plate. The actuator applies vibration to the acoustic vibration plate to play back sound. The speaker apparatus enables a sound image to uniformly spread over the entire plate surface of the acoustic vibration plate. In addition, the entire speaker apparatus can be made compact.

Abstract: A low frequency transducer arrangement includes a substantially cylindrical structure surrounding a pole piece. The pole piece and the substantially cylindrical structure define a substantially cylindrical air gap therebetween. Two opposite ends of the air gap are both open and separated from each other in an axial direction. A first magnet is disposed in either the pole piece or the substantially cylindrical structure. A second magnet is separated in the axial direction from the first magnet by a middle magnetic gap. The second magnet is disposed in either the pole piece or the substantially cylindrical structure. The first and second magnets provide flux in a same direction in the middle magnetic gap. A top magnetic gap is disposed axially adjacent the first magnet and opposite the middle magnetic gap. A bottom magnetic gap is disposed axially adjacent the second magnet and opposite the middle magnetic gap. A voice coil is at least partially disposed in the air gap and operates in the middle magnetic gap.

Abstract: A sound device includes a full-gamut single-body sound membrane, a voice coil, a dust cover, and an assembly structure. Materials of different kinds of beating degrees are applied at different positions of the sound membrane. A structural intensity of materials is changed radiantly, radially and gradually, from an innermost rim of the sound membrane toward an outermost rim of the sound membrane, such that the structural intensity gradually decreases from the innermost rim toward the outermost rim, to satisfy requirements of sounding for the full-gamut of audible frequency.

Abstract: A speaker diaphragm is configured by a compound mixed with resin and bamboo fiber. The diaphragm satisfying the advantage of the bamboo fiber of high sound quality and a large degree of freedom in the setting of the characteristic value of the diaphragm and the advantage of the diaphragm made of a resin with improved humidity resistance reliability and strength, excellent external appearance, and enhanced productivity and dimension stability is obtained.

Abstract: A speaker diaphragm is configured by a compound mixed with resin and bamboo fiber. The diaphragm satisfying the advantage of the bamboo fiber of high sound quality and a large degree of freedom in the setting of the characteristic value of the diaphragm and the advantage of the diaphragm made of a resin with improved humidity resistance reliability and strength, excellent external appearance, and enhanced productivity and dimension stability is obtained.

Abstract: A device includes a substrate and a transducer attached to the substrate, wherein the substrate includes a surface to which the transducer is attached and at least one edge member extending along at least a portion of the outside edge of the surface. The surface can be a generally planar surface. The edge member is stiffer than the surface. In several embodiments, the transducer is adapted to vibrate. The transducer can, for example, be selected from the group consisting of a piezoelectric transducer, an electrostrictive transducer and a magnetostrictive transducer. Preferably, the transducer is attached to the surface of the substrate by a metallic bonding agent and, more particularly, by welding.

Abstract: A speaker includes a magnetic circuit forming a slit-like magnetic gap, a frame that houses and holds the magnetic circuit, a diaphragm attached to the frame so as to be capable of vibrating, a voice coil unit that is placed so as to pass through substantially the center of the magnetic gap, and has its one end coupled to the diaphragm, and a damper attached to the frame to support the other end of the voice coil unit. The voice coil unit has a planar-type coil bobbin section, and a voice coil section having a coil member wound in a planar track shape and disposed so as to extend through the coil bobbin section from one side to the other side and from the other side to the one side.

Abstract: A loudspeaker mounting assembly includes a frame, a sleeve, and a tilt-angle adjustment mechanism. The frame may include an outer frame, an inner frame rotatable about a frame axis relative to the outer frame, and a frame wall extending away from a rear side. The sleeve is coupled to the inner frame at a pivot axis and is tiltable to a plurality of tilt angles relative to the inner frame. The tilt-angle adjustment mechanism is engageable with the sleeve to enable selection of a desired tilt angle. A loudspeaker may be mounted to the sleeve such that the loudspeaker may be swiveled about the frame axis and tilted about the pivot axis.

Abstract: A speaker includes a holder forming a hollow space, a magnetic system received in the hollow space, a suspension assembled with the holder and defining a supporting portion, a pair of fixing portions far away from the supporting portion and fixed on the holder, and a plurality of arm portions connecting the supporting portion and the fixing portions, respectively. The arm portions defines a pair of outer arm portions protruded outwardly from the circumference of two ends of the supporting portion and a pair of inner arm portions extending from the circumference of said two ends of the supporting portion and set in space with respect to the inner arm portions, respectively.

Abstract: A micro-speaker includes a yoke, a magnet assembly attached to the yoke, a voice coil, and a diaphragm connected with the voice coil. The yoke defines a bottom wall, and a number of sidewalls extending upwardly from the bottom wall. The magnet assembly includes a main magnet positioned on the bottom wall, and a number of secondary magnets positioned on tops of the sidewalls.

Abstract: An electroacoustic transducer is disclosed. The electroacoustic transducer includes a frame forming a hollow space, an elastic plate mounted on the frame, a vibrating member suspended in the hollow space by the elastic plate, a diaphragm arranged facing the vibrating member, a voice coil positioned on the diaphragm. The vibrating member includes a yoke defining a bottom wall, a side wall extending upwardly and perpendicularly from an outer periphery of the bottom wall, a lapel extending vertically from the side wall. A width of the lapel is greater than that of the side wall or the bottom wall.

Abstract: A multi-layer armature for a moving armature receiver. The armature includes a first armature layer and a displacement region. The first armature layer includes a first surface and a second armature layer having a second surface positioned adjacent to the first surface. The displacement region provides relative displacement between the armature layers. The multi-layer construction of the armature in combination with the displacement region creates considerable design freedom in choosing armature geometry outside conventional bounds posed by the above-mentioned constraint between armature cross-sectional area and its mechanical stiffness. The design freedom can be applied to achieve numerous performance benefits for the moving armature receiver such as higher electroacoustic conversion efficiency, increased maximum sound pressure output or smaller overall length of the multi-layer armature.

Abstract: A speaker device for a portable terminal includes: an electromagnetic wave noise shield member mounted on a circuit board; a speaker unit mounted on the electromagnetic wave noise shield member, the speaker unit producing sound; and a resonance space formed by the electromagnetic wave noise shield member and the circuit board, the sound produced from the speaker unit being partially provided to the resonance space. Since the speaker device configured as described above secures a resonance space using an electromagnetic wave noise shield member mounted on a circuit board in a portable terminal, it is possible to improve sound quality while maintaining the size of the portable terminal to be the same as a separate resonance space is not required.

Abstract: An audio device includes a first audio path with a loudspeaker for reproducing an audio signal, and a second audio path. The second audio path includes in series a band-pass filter for filtering an audio signal, a detector for detecting the amplitude of the band-pass filtered audio signal, a multiplier for multiplying a periodic signal by the amplitude of the band-pass filtered audio signal, and a vibration device for reproducing the multiplied periodic signal. The frequency of the periodic signal is substantially equal to the resonance frequency of the vibration device.