Abstract: [Problem to be Solved] To provide a high-sensitive compact vibration pickup microphone, suitably used as a talking microphone in high ambient noise environments or as a speech recognition input microphone, with high microphone sensitivity, resistance to sliding noise, and insensitivity to external noise and vibration.

Abstract: An earphone 1, which adopts the drum air power system the invention, includes at least a drum 5 composed of a drum-shaped casing 2, a front head 3 located on the front part of the casing 2, a rear head 4 located on the rear part of the casing 2, an inner-drum space 5a defined by the casing 2, the front head 3, and the rear head 4. Earphone 1 also comprises a driver unit 6 installed inside the drum 5 and equipped with an external sound conducting part 6a and an internal sound conducting hole 6b. The front head 3 and the rear head 4 resonate in response to driving by the driver unit 6 so that the low pitch sounds B and C are output in addition to the full range sound formed from the external sound conducting part 6a. This structure lowers the minimum resonance frequency and increases the sound pressure.

Abstract: The present invention is an acoustic traveling wave tube system for propagating a directional acoustic wave comprising an acoustic traveling wave tube having a cylindrical shape with a load on one end of the tube, a plurality of excitation rings positioned around a circumference of the tube and spaced at predetermined intervals along a length of the tube and a microprocessor having a database containing a plurality of waveforms representative of acoustic signals. The microprocessor energizes one of the plurality of excitation rings to form an acoustic wave, sequentially energizes one or more of the remaining excitation rings along the length of the tube to amplify the acoustic wave as the acoustic wave travels along the length of the tube, and propagates the acoustic wave from an end of the tube opposite the load as a shaped directional acoustic wave.

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 loudspeaker assembly, including an acoustic waveguide; an acoustic driver mounted in the waveguide so that a first surface radiates sound waves into the waveguide so that the sound waves are radiated from the waveguide; and an acoustic volume acoustically coupled to the acoustic waveguide for increasing the amplitude of the sound waves radiated from the acoustic waveguide.

Abstract: Provided is an enclosure including a rear chamber, a speaker unit chamber disposed adjacent to the rear chamber and connected to the rear chamber such that air flows between the speaker unit chamber and the rear chamber, a front chamber disposed adjacent to the speaker unit chamber and connected to the speaker unit chamber such that air flows between the speaker unit chamber and the front chamber, and a duct having a first side connected to the front chamber such that air flows between the front chamber and the duct and a second side opened to the outside, wherein the rear chamber, the speaker unit chamber, the front chamber, and the duct are disposed between a first plate and a second plate that are spaced apart from each other.

Abstract: A loudspeaker assembly comprises a base supporting at least one electro-acoustic transducer and at least one waveguide segment detachably supported by the base.

Abstract: An electronic device may include a substrate and an acoustic actuator mounted on a surface of the substrate. More particularly, the acoustic actuator may be configured to generate displacements along a direction parallel with respect to the surface of the substrate in response to an electrical signal applied thereto. A speaker box may define an acoustic volume, and the speaker box may include a speaker box wall with a speaker box opening therethrough adjacent the acoustic actuator. A speaker membrane may be provided across the speaker box opening adjacent the acoustic actuator, and the speaker membrane may be mechanically coupled to the acoustic actuator so that the speaker membrane is configured to deflect responsive to displacements generated by the acoustic actuator. Related methods are also discussed.

Abstract: A method and apparatus for a multi-chamber ported stereo speaker is disclosed. The stereo speaker is a single unit with multi-chambers in an enclosure box. The multi chamber ported speaker comprises an enclosure housing a shared acoustic chamber having an external port for allowing air external of the enclosure box to flow into the shared acoustic chamber, and at least two additional chambers comprising a corresponding internal port in each additional chamber for forming an air pass from each additional chamber with the shared chamber, each additional chamber comprising a corresponding driver mounted through a wall of the chamber and enclosure box for forming the ported speaker.

Abstract: An acoustic transducer radiates a sound wave into a medium, and includes: a shaft member which extends at a center portion of the acoustic transducer; first and second cylindrical acoustic radiation plates which have a cylindrical shape, a central axis of the first and second cylindrical acoustic radiation plates agreeing with the longitudinal axis of the shaft member, the first and second cylindrical acoustic radiation plates alternately arranged in a direction of the central axis; a plurality of connection members which have a ring shape, and connect adjacent first and second acoustic radiation plates to each other; a plurality of bending vibration plates each of which connects the shaft member and one of the connection members to each other; and a plurality of vibrators which are provided on the bending plates.

Abstract: An electronic device may include a printed circuit board and a speaker box defining an acoustic volume between spaced apart first and second speaker box walls with the first speaker box wall being between the second speaker box wall and the printed circuit board. A loudspeaker may be coupled to the first speaker box wall, and the loudspeaker may include an acoustic actuator that is configured to generate displacements in response to an electrical signal applied thereto. The loudspeaker may further include a speaker membrane that is mechanically coupled to the acoustic actuator and that is configured to deflect in directions toward and away from the second speaker box wall responsive to displacements of the acoustic actuator. Related assemblies and methods are also discussed.

Abstract: A speaker component for a portable electronic device which accepts a receiver and redirects the sound emitted from the receiver toward the speaker hole in the device housing is disclosed. The receiver may be oriented such that sound is directed away from the speaker hole to reduce the footprint of the receiver within the device housing. A channel of the speaker component may redirect or port the sound to the speaker hole. Accordingly, embodiments provide more flexibility for positioning of the speaker hole and the receiver with respect to the device housing. The speaker component may also have a self-contained back volume chamber adjoining the receiver which does not include portions of the device housing or other components of the portable electronic device, thereby improving the sound quality of the sound emitted from the receiver and providing more flexibility as to the size and shape of the back volume chamber.

Abstract: An earphone is disclosed that is used in connection with reproducing audio sounds that are supplied from an audio-frequency source. The earphone includes a housing that includes a boot assembly positioned in the housing. A first audio driver is positioned in the boot assembly such that a first output of the first audio driver is in acoustic communication with a mixing chamber. A second audio driver is also positioned in the boot assembly such that a second output of the second audio driver is in acoustic communication with a chamber in the boot assembly. A tubular needle is positioned in the boot assembly having a first end in acoustic communication with the chamber and a second end in acoustic communication with the mixing chamber.

Abstract: A microphone unit includes: a housing which has an inner space; a partition member which is provided in the housing and divides the inner space into a first space and a second space, the partition member being at least partially formed of a diaphragm; and an electrical signal output circuit which outputs an electrical signal based on vibrations of the diaphragm. In the housing, a first through-hole through which the first space communicates with an outer space of the housing and a second through-hole through which the second space communicates with the outer space are formed.

Abstract: A wireless mobile electronic device includes a first housing and a first acoustic chamber disposed within the first housing. A sound generator, within said first housing, is acoustically coupled to the first acoustic chamber. Additionally, a first acoustic port defines an opening into the first acoustic chamber. The acoustic port includes a first mating structure configured for mating with a second mating structure of a second acoustic chamber, exclusive of said first housing.

Abstract: A child soothing device includes a frame comprising a structural support, a housing coupled to the structural support and comprising a cover with an opening, and a speaker including a speaker driver and a speaker chamber. The speaker driver has a diaphragm disposed relative to the opening in the cover for external sound wave propagation via displacement of the diaphragm, and the speaker chamber has a volume defined by the housing and in communication with the diaphragm for internal sound wave propagation via the displacement of the diaphragm. The device further includes a partition within the housing to further define the volume of the speaker chamber. The volume may include a region obliquely oriented relative to the diaphragm to support a low frequency response of the speaker.

Abstract: A speaker system which includes a housing and a linear array of a plurality of sound-generating transducers. A housing is in the form of a cylinder having a longitudinal axis and substantially circular cross-section. The linear array of sound-generating transducers are mounted upon a substantially planar chord configured within a sidewall of the cylinder.

Abstract: A speaker capable of suppressing deterioration of acoustic efficiency while allowing miniaturization of the speaker includes a first unit (20) and a second unit (21) each of which outputs sound. The first unit (20) includes: a diaphragm (25) which vibrates back and forth to radiate sound; and plural suspensions (26a, 26b, 26c, 26d) which support, at different positions, an outer periphery of the diaphragm (25). At least one of air passages (35a, 35b) for channeling sound from the second unit (21) to the outside is provided between the plural suspensions (26a, 26b, 26c, 26d).

Abstract: A speaker system includes a case having a receiving chamber; a variable mechanism received in the receiving chamber for dividing the receiving chamber into a first chamber and a second chamber and being capable of varying a volume of the first chamber; and a speaker unit is received in the first chamber and defining an acoustic port facing an exterior of the case. The separating wall alternatively inserts into one of the receiving member for placing the separating wall precisely at specific locations. Thus, it is easy to vary the volume of the first chamber for achieving an excellent acoustic capability of the speaker system.

Abstract: A speaker device may include a substrate, a membrane above the substrate, and an electrode above the membrane, a plurality of first supporting members, and a plurality of second supporting members. The second chamber is enclosed between the membrane and the substrate, and the first chamber is enclosed between the electrode and the membrane. The first supporting members are provided in the first chamber space and may space the membrane apart from the electrode. The second supporting members are provided in the second chamber space and may space the membrane apart from the substrate.

Abstract: A speaker apparatus includes a speaker and a sound box. The sound box is shaped like a wine barrel and includes arced side boards and parallel top and bottom boards coupled to upper and lower ends of the side boards, respectively. The sound box is divided by at least an isolating board into air chambers interconnected with one another via at least an air aperture formed in the isolating board, and at least an air venting hole is formed through at least one of the side boards so as to communicate the air chambers with the outside. The speaker is installed on the top board via an installation hole formed therein. The interconnected air chambers and side boards produce air cushions corresponding to resonant frequency sections of the speaker, thereby enabling the speaker to reproduce original audio sounds without interfering with a successively formed air cushion.

Abstract: A sound system which has, for example, a radio, a cassette and a CD player is usually already installed in cars as standard or as an option. In addition, a better sound system includes a box system which has a tweeter and a woofer. In order to provide a speaker box which is suitable particularly for dispensing frequencies below 150 Hz and at the same time has neat pulses accompanied at the same time by little distortion, pulse dynamics and is highly effective, a sound transducer (10) is introduced into the supporting structure of the vehicle. This takes place in such a manner that subcompartments which are separated from each other adjoin each of its two membrane sides. In this case, the two subcompartments of the speaker box are formed by at least two elements (2, 3, 4) of the supporting structure of the vehicle (1).

Abstract: A method of improving the “tight space” usefulness of a unidirectional microphone of the type having an otherwise screw-together headpiece and handle, includes the steps of: (a) fabricating an adapter having male- and female-threaded ends and a cavity of a specified volume that extends between these ends, and where each of these ends has a centerline and these intersect at a prescribed angle, (b) fabricating the adapter's cavity so that its volume is approximately equivalent to that of the volume of handle's acoustic chamber, and (c) connecting the adapter's male-threaded end to the handle and its female-threaded end to the headpiece in such a manner as to not appreciably change the frequency response characteristics of the microphone.

Abstract: A performance venue with a main speaker system is provided having a target coverage area within the performance venue. A performance area is located within the performance venue outside the target coverage area of the main speaker system. A low frequency directed audio source is positioned with respect to the performance area for active cancellation of low frequency sound spilling over into the performance area from the main speaker system. Control of the low frequency directed audio source is effected by an audio sensor is located in the performance area for generating an output correlated with low frequency spill over into the performance area.

Abstract: A speaker device for a portable terminal including a first housing and a second housing coupled to the first housing and rotating towards or away from the first housing while facing the first housing. The speaker device includes a speaker unit mounted in the second housing, first sound output holes formed in the second housing, and second sound output holes formed in the first housing. When the second housing is folded to the first housing, a sound output from the speaker unit is guided into the first housing through the first sound output holes, travels inside the first housing and is output through the second sound output holes. In the speaker device for the portable terminal, the speaker unit and the resonating space are separately positioned in the housings, thereby providing a mellow volume and a high-quality sound and contributing to slimness of the portable terminal.

Abstract: A speaker module for a personal communication device includes two transducers for generating sound on the basis of an electrical signal. One transducer outputs sound to the surroundings from a sound output thereof and the other transducer outputs sound to the surroundings via the first transducer. In this manner, two transducers require only one sound output. The sound from the second transducer may be transmitted through and filtered by an opening in a diaphragm of the first transducer. Filtering elements may be provided between the two transducers.

Abstract: A speaker system is presented. The speaker system has a front speaker driver, a shroud mounted to the front speaker driver substantially encasing a cylinder volume on a rear portion of the front speaker driver. A rear speaker driver having similar dimensions to the front speaker is axially aligned with the front speaker driver and secured at a determined distance behind the front speaker driver and the shroud providing an air gap between the shroud and the rear speaker driver. An acoustically treated enclosure encloses a volume on a rear portion of the rear speaker driver. Electrical connections connect the front speaker driver and the rear speaker driver to terminals for connection to an external driving source such that like excursions occur on the front speaker driver and the rear speaker driver when the external driving source is operable and the front speaker driver functions in an open baffle system.

Abstract: A portable speaker having at least one driver mounted in a first enclosure and a second enclosure separate from the first enclosure and having pivotally mounted to it the first enclosure. The second enclosure has all electronics, controls and a battery compartment. The first enclosure is moveable relative to the second enclosure between a first configuration and a second configuration, the at least one driver being protected by the second enclosure when the first enclosure is in the first configuration.

Abstract: A system and method for reducing baffle vibration includes balancing an inertial force generated by two or more moving diaphragms and balancing an acoustic pressure acting on a housing supporting the two or more moving diaphragms such that a net force acting on the baffle is substantially zero. The acoustic force acting on the housing may be balanced independently of the inertial force balance. In another configuration, the acoustic force acting on the housing may be balanced by a non-zero net inertial force.

Abstract: A mobile communication device is provided. The mobile communication device includes a terminal body, and a speaker module located in the terminal body. The speaker module includes an enclosure located in the terminal body, the enclosure defining a chamber therein, and a speaker having a front surface and a rear surface, the speaker being located in the enclosure such that the front surface of the speaker is exposed from the enclosure and the rear surface thereof is positioned within the chamber, to allow a sound generated from the rear surface to resonate within the chamber. A mutual interference between the sound generated from the front side of the sound emission part and the sound emitted from the rear side thereof can be reduced to thereby improve the performance of the middle and low sound.

Abstract: A system includes a chair having an electrical connection to electrically connect the chair to a gaming device and a speaker package incorporated into the chair and coupled to the electrical connection. The speaker package includes a speaker mounted to a central member between a first shell defining a front cavity and a second shell defining a back cavity.

Abstract: In a low frequency transducer system a multi-compression chamber, inverse horn structure is employed in combination with a resonance-distortion filter chamber. The filter chamber effectively expands the effective enclosure volume at low frequencies and connected to one of the compression chambers filter parasitic resonances and distortion and allowing the system to more efficiently reproduce low frequencies while being able to use smaller diameter transducers and maintaining good system sensitivity. Compression chambers are organized for constant or continuous compression on a section-by-section basis throughout the inverse horn system.

Abstract: A mobile phone and an acoustic box structure thereof are provided. The mobile phone includes a shell containing a printed circuit board (PCB) and a hidden antenna therein. The acoustic box structure is disposed between the PCB and the hidden antenna. The acoustic box structure includes a main body, a loudspeaker accommodated in the main body and a frame located between the PCB and the main body. Due to the design of the frame, a hermetic space is framed between the PCB and the main body, thereby preventing sound waves generated by the loudspeaker from leaking out via a gap between the main body and the PCB. Furthermore, the frame made of shockproof materials decreases the resonant transfer between the PCB and the loudspeaker. Consequently, the quality of the sound made by the mobile phone is improved.

Abstract: An earphone is disclosed that is used in connection with reproducing audio sounds that are supplied from an audio-frequency source. The earphone includes a housing that includes a boot assembly positioned in the housing. A first audio driver is positioned in the boot assembly such that a first output of the first audio driver is in acoustic communication with a mixing chamber. A second audio driver is also positioned in the boot assembly such that a second output of the second audio driver is in acoustic communication with a chamber in the boot assembly. A tubular needle is positioned in the boot assembly having a first end in acoustic communication with the chamber and a second end in acoustic communication with the mixing chamber.

Abstract: Micro-speaker assemblies and mobile terminals including micro-speaker assemblies are provided. The micro-speaker assemblies include a micro-speaker positioned in a housing. A first forward tuning volume is positioned adjacent a front face of the micro-speaker. A passageway extends from the first forward tuning volume to an opening in the housing. A second forward tuning volume in fluid communication with the passageway is positioned at a location between the first forward tuning volume and the opening in the housing. The second forward tuning volume, the first forward tuning volume and the passageway define a double-resonator that tunes a frequency response of the micro-speaker. Methods for tuning micro-speakers are also provided.

Abstract: An in-wall speaker system having at least one pair of active transducers mounted in a wall section. The active transducers may be mounted in at least one enclosure. Each active transducer has a sound radiating surface. Each active transducer is also mounted substantially perpendicular to a surface of the wall section with the sound radiating surfaces substantially parallel to each other. The sound radiating surfaces may be facing each other or away from each other. The in-wall speaker system may also include one or more pairs of passive radiators to generate sound from sound pressure generated by the active transducers. The pairs of speakers in the wall section may be mounted vertically or horizontally within the wall, with a slot or a vent at the opening at the space between the speaker pairs.

Abstract: An implanted microphone is provided that has reduced sensitivity to vibration and attendant acceleration forces to differentiate between desirable and undesirable components of a transcutaneously received signal. More specifically, the microphone utilizes an output that is indicative of acceleration forces acting on the implanted microphone to counteract and/or cancel the effects of acceleration-induced pressures in an output signal of a microphone diaphragm. In one arrangement, a microphone having two diaphragms pneumatically cancels acceleration pressures. In this arrangement, a first diaphragm receives and generates a response to commingled acoustic and acceleration forces and a second diaphragm is substantially isolated from the acoustic forces. That is, the second diaphragm generates a response to acceleration forces. The displacements of the first and second diaphragms are pneumatically combined.

Abstract: One mode of the present invention provides an electroacoustic transducer composed of a multifaced diaphragm assembly and a multifaced speaker housing assembly that is housed inside the multifaced diaphragm assembly. The multifaced speaker housing is configured by combining the outer peripheral surface of a plurality of individual speaker drive units into a nearly spherical shell. The multifaced diaphragm assembly, which has thereinside the multifaced speaker housing assembly, is configured to have a plurality of regular pentagonal diaphragm segments that are combined together into a nearly spherical shape shell, and a plurality of speaker drive units opposing the diaphragm segments from inside in one-to-one relation. Each speaker drive unit has a bobbin, the one end portion of which is adhered to the center portion of the inner surface of each diaphragm segment.

Abstract: According to one embodiment, a front frame forms a cabinet, and a display screen of an image display unit is arranged to be exposed from an opening at the center thereof. A frame forming portion is located at the lower part of the front frame, and sound emitting units which open elongatedly in a longitudinal direction of the frame forming portion are formed. A cabinet surface is formed continuously to the bottom side of the opening and is tilted and retreated while being bent in a direction of the back face of the front frame as it goes downwards.

Abstract: A speaker module and a mobile device having the speaker module are provided herein. The speaker module includes a speaker unit and a speaker box. The speaker box has a wall defining an aperture receiving the speaker unit therein. The speaker box has a first speaker chamber, a second speaker chamber and a connecting section connecting the first speaker chamber and the second speaker chamber. The cross-sectional height of the space of the connecting section is lower than that of the first speaker chamber or the second speaker chamber. In other option, the space of the connecting section is smaller than that of the first speaker chamber or the second speaker chamber.

Abstract: In a communication device (1) that is designed to deliver sound, in an against the-ear mode, into a space (22) bounded by the ear and, in an away-from-the-ear mode, into an acoustic free space, a loudspeaker (3) is provided for generating the sound and a holding device (2) is furthermore provided, which holding device (2) comprises a first holding-device region (16) via which, in the against-the-ear mode, the sound generated by the loudspeaker (3) can be delivered without hindrance by the ear and which holding device (2) comprises a second holding-device region (15A) that does not comprise the first holding-device region (16) and via which, in the against-the-ear mode, the sound generated by the loudspeaker (3) can be fed to the space (22) bounded by the ear and a first sound-conveying device is furthermore provided with whose aid the sound generated by the loudspeaker (3) can be conveyed, in the away-from-the-ear mode, through the first holding-device region (16) into the acoustic free space, and a second so

Abstract: A speaker set (10) includes an enclosure (11) extending two spaced supporting portions (118) from a bottom side thereof for contacting with a supporting member (20); a woofer (12), two mid-frequency speakers (13), and two tweeters (14) are disposed in the enclosure; a circuitry electrically connects with the woofer, the mid-frequency speakers, and the tweeters; two woofer chambers (121, 123) are disposed at two opposite sides of a diaphragm of the woofer. One of the woofer chambers is defined between the bottom side of the enclosure, the supporting portions of the enclosure and the supporting member, whilst the other one of the woofer chambers is defined in the enclosure. Sound generated by the woofer emanates to a surrounding environment through both the woofer chambers, wherein the enclosure defines a plurality of venting holes (122) communicating with the other one of the woofer chambers.

Abstract: A sound generator like a guitar supplies an electrical out put to operate speakers that are mounted in a chassis. The electrical output is divided into three frequency ranges, separately amplified and delivered to speakers mounted in a three separate enclosures each acoustically isolated from the other.

Abstract: A transducer assembly may include a first transducer having a first front volume, a first back volume and a first port acoustically coupled to the first front volume; and a second transducer having a second front volume, a second back volume and second port acoustically coupled to the second front volume. The first front volume and the second front volume are acoustically coupled to increase the effective back volume of both the first transducer and the second transducer. An optional signal processing circuit may be used to control the output of the first transducer based upon a signal received from the second transducer.

Abstract: An electric-acoustic transducer/housing assembly includes an electric-acoustic transducer and a housing within which the electric-acoustic transducer is arranged. The electric-acoustic transducer includes a casing, a first and second vibratory plates transversely mounted within the casing, and an exciter disposed between the first and second vibratory plates and operated to vibrate the first and second vibratory plates. The first vibratory plate cooperates with the exciter to define a first inner chamber therebetween. A sound pipe extends outwardly from the casing and is adapted to allow the first inner chamber to be communicated with the outside of the housing. The second vibratory plate cooperates with the exciter to define a second inner chamber therebetween. The casing has a through sound hole through which the second inner chamber is communicated with the outside of the casing. The sound pipe is kept out of communication with the through sound hole.

Abstract: A method and a loudspeaker construction (10), in which loudspeaker construction spherical acoustic wave fronts emitted by the diaphragms (12) of speaker elements (11) are transformed into a uniform, planar acoustic wave front. The loudspeaker construction (10) comprises a plane wave channel (20), in the surface (26) of which plane wave channel directed towards the diaphragm (12) there are adjacent sound inlet apertures (24) for transmitting acoustic waves into ducts (23) and, on the opposite side (22) of the plane wave channel, there are outlet apertures (25) for transmitting acoustic waves from the ducts into a horn portion (30). The ducts (23) taper so that the width (B) of the outlet apertures located in a row on the side of the horn portion is less than half the diameter (D) of the diaphragm.

Abstract: The low frequency efficiency of a hearing instrument receiver can be improved by increasing the unoccupied rear volume. The receiver may be configured with one or more motor and diaphragm assemblies. The receiver may also be fabricated using multiple, conventional receivers with an added housing to create the increased, unoccupied rear volume.

Abstract: A compact loudspeaker enclosure combines planar type devices for high frequency sound reproduction and cone type active devices for low frequency sound reproduction. The low frequency cone type transducers are mounted in baffles between forward and rear enclosed spaces and thus do not directly radiate into the environment. The first enclosed space is acoustically coupled to the environment by the planar device which is mounted between the first enclosed space and the environment with one major face mounted to radiate either directly into the environment or to be horn loaded. The planar operates as a passive radiator to the LF devices at low frequencies and an active device above a crossover frequency.

Abstract: The disclosure relates to a satellite speaker system wherein the horn mouth of a main speaker, typically of a folded horn design, is divided by braces into satellite speaker storage chambers. This allows the satellite speakers to be placed into the storage chambers for storage and transportation, and then easily removed and placed into their remote locations for a show, performance or gig.

Abstract: A speaker set (20) for an electronic product (100) includes a hollow shell (60), and a loudspeaker (50) accommodated in the shell. The shell includes at least a spacing plate (68) which divides an inner space of the shell into a first resonance chamber (61a) and a second resonance chamber (61b). The loudspeaker includes first tone holes (52) communicating with the first resonance chamber and second tone holes (54) communicating with the second resonance chamber. The second resonance chamber communicates with the first resonance chamber via at least an inverted hole (69) defined in the at least a spacing plate. The first resonance chamber communicates with a surrounding environment so that sound emitted from the first and second tone holes of the loudspeaker can be transferred to the surrounding environment.