Abstract: A sound reproduction screen includes: at least one cell including a vibrator which receives and is vibrated by an ultrasonic signal carrying an audible signal, and a medium which has nonlinear response characteristics with respect to a vibration of the vibrator; and a screen containing the at least one cell which is distributed in a matrix structure, wherein the vibrator of the cell includes an elastic body that is vibrated by the ultrasonic signal and reflects the audible signal separated from the ultrasonic signal according to the nonlinear response characteristics of the medium, and an asymmetrical body that is connected with the elastic body and vibrates in the medium.

Abstract: Disclosed herein is a speaker system including a speaker unit with a speaker body incorporated therein; and a speaker panel disposed on the front side of the speaker unit; wherein the speaker panel has a multiplicity of fine holes permitting a sound of the speaker body to pass therethrough, and has an opaque part hiding the presence of the speaker unit, and a transparent part in the periphery of the opaque part.

Abstract: A device is provided for actuating a membrane arranged in an opening to a space, and a vehicle having such a device. The membrane has a first surface and a second opposite surface, and is limited by an edge area. The device includes a first strip to be attached to the second surface of the membrane in the edge area, and a second strip to be attached to a surface of a frame portion extending around the opening. An exchanging member is arranged between and connecting the first strip and the second strip. An actuating member is arranged to transfer a reciprocating primary movement to the exchanging member converting the primary movement to a reciprocating secondary movement, which has a longer length of stroke than the primary movement and acts on the strips to move towards and away from each other.

Abstract: The invention relates to so-called panel loudspeakers (11) working according to the multiresonance principle. Said loudspeakers are generally formed by a core layer (13) and at least one outer layer (14.o, 14.u). The outer layers (14.o, 14.u) are connected to the core layer (13). A periphery is also provided (12) enclosing the panel loudspeaker (11) at a lateral distance (A). The panel loudspeaker is connected to the periphery (12) by means of connecting elements (17, 17?). Although good reproduction results can be obtained in the mid and high audio frequencies with the panel loudspeakers (11) described above, undesired large panel surfaces are known to be required for good low frequency reproduction. When such panel surfaces are not used, the lowest panel resonances ensuring bass reproduction are shifted towards the midfrequencies. Hence, the invention aims at providing a panel loudspeaker (11) exhibiting improved acoustic reproduction in the low frequency range despite a relatively smaller panel surface.

Abstract: A vehicle headliner includes electromagnetic drivers for sonically driving a member or a layer of the headliner. A foam beam is shaped around a driver transducer connection area that holds one or more driver connectors. A cover may be maintained over the shaped foam beam to protect against entry of dust and other debris into the driver and the transducer connection area that receives the driver.

Abstract: Acoustic device including a member extending transversely of its thickness and capable of sustaining bending waves at least over an intendedly consequentially acoustically active area of the transverse extent of said member, the member having, by reason of orderly design methodology disclosed and claimed, a distribution of resonant modes of its natural bending wave vibration at least over said area that is dependent on values of particular parameters of said members, including geometrical configuration and directional bending stiffness(es), which values have been selected to predetermine said distribution of natural resonant modes being consonant with required achievable acoustic action of said member for operation of said device over a desired operative acoustic frequency range.

Abstract: The invention relates to a planar loudspeaker comprising a light, thin soundboard (2) which may be energized to produce multiply-reflected bending waves, a surrounding frame (3) holding the soundboard (2) in an articulated, shear-resistant manner; at least one driver (6, 7, 9, 10) connected to the soundboard (2) to energize the soundboard (2); and at least one bridge (13, 16, 18, 20, 22, 25), rigidly connecting the at least one driver (6, 7, 9, 10) to the frame (3), wherein the bridge or at least one of the bridges (13, 16, 18, 20, 22, 25) is connected to the damping board (14).

Abstract: A loudspeaker assembly comprising a visual display screen, a resonant panel-form member positioned adjacent to the display screen, and a vibration exciter to cause the panel-form member to resonate as an acoustic resonator. At least a portion of the panel-form member is transparent, through which portion the display screen is visible.

Abstract: A flat acoustic conversion device includes two magnets disposed so that their magnetic poles face upward arid are adjacent to or in contact with one another, and the magnetic pole faces of different polarities arc disposed alternately; a vibrating member disposed on the top surface of the yoke; coil pairs wound in helical form and disposed at front and reverse surfaces of the vibrating membrane; such that magnetic flux traveling in a direction substantially parallel to a surface of the vibrating membrane becomes a maximum, and interlinks with the coil pairs. When current is supplied to the coils, a direction of force which the current receives from a magnetic field is substantially orthogonal to the surface of the vibrating membrane, and force in a direction along the surface of the vibrating membrane becomes extremely low. Thus, noise components can be reduced such that sound quality can be improved.

Abstract: The present invention intends to provide a piezo-electric speaker which can generate a sound from the low frequency range to the high frequency range as well as transmit the acoustic vibration to a sound-board with a high efficiency. This is achieved by providing a piezo-electric speaker comprising a piezo-electric member generating a strain according to an electric signal applied thereto; a piezo-electric vibration plate converting the strain to the acoustic vibration; and a sound-board resonating to the acoustic vibration; the piezo-electric plate being supported on the sound-board; the acoustic vibration caused by the piezo-electric vibration plate being propagated from the sound-board to the ambient air to generate a sound.

Abstract: Acoustic device including a member extending transversely of its thickness and capable of sustaining bending waves at least over an intendedly consequentially acoustically active area of the transverse extent of said member, the member having, by reason of orderly design methodology disclosed and claimed, a distribution of resonant modes of its natural bending wave vibration at least over said area that is dependent on values of particular parameters of said members, including geometrical configuration and directional bending stiffness(es), which values have been selected to predetermine said distribution of natural resonant modes being consonant with required achievable acoustic action of said member for operation of said device over a desired operative acoustic frequency range.

Abstract: A panel-shaped loudspeaker comprising a panel (1) having a first main surface (1A) and a second main surface (1B) parallel to the first main surface and further comprising an exciter (3) positioned at the first main surface. When the exciter is energized the panel is capable of sustaining bending waves and has a distribution of resonant modes of its natural bending wave vibration, which results in an acoustic radiation. The loudspeaker has a tuning element (17) extending near the second main surface of the panel and positioned opposite the exciter so as to form a resonant cavity (18) between the panel and the exciter.

Abstract: A bending wave loudspeaker includes a transparent acoustic radiator capable of supporting bending wave vibration and an electromechanical force transducer mounted to the acoustic radiator to excite bending waves in the acoustic radiator to produce an acoustic output. The transducer has an intended operative frequency range and includes a resonant element having a frequency distribution of modes in the operative frequency range and a coupler for mounting the transducer to the acoustic radiator. The loudspeaker may be incorporated in a telephone handset or a visual display unit.

Abstract: A transducer (14) for producing a force which excites an acoustic radiator, e.g. a panel (12) to produce an acoustic output. The transducer (14) has an intended operative frequency range and comprises a resonant element which has a distribution of modes and which is modal in the operative frequency range. Parameters of the transducer (14) may be adjusted to improve the modality of the resonant element. A loudspeaker (10) or a microphone may incorporate the transducer.

Abstract: A sound reproducing apparatus includes a display unit, a board 22, a diaphragm panel 23, and an electroacoustic transducer 26. The display unit displays an image on a display surface. The board 22 is composed of a material which transmits visible light and arranged such that a first space is provided between the display surface of the display unit and the board 22. The diaphragm panel 23 is composed of a material which transmits visible light and arranged on the opposite side of the board 22 from the display unit such that a second space is provided between the board 22 and the diaphragm panel 23. The electroacoustic transducer 26 emits sound into the second space.

Abstract: A bending wave panel-form acoustic radiator formed from sheet material to define an acoustically active area and having at least one integral stiffening member in the form of a corrugation extending out of the plane of the sheet and at least partially across the acoustically active area of the radiator, which stiffening member is of substantially U-shaped cross section. Also disclosed is a method of making a bending wave panel-form acoustic radiator, comprising forming a sheet into a panel having at least one integral corrugation member extending out of the plane of the sheet and at least partly across the sheet and of substantially U-shape cross-section, to stiffen the sheet to have a desired ability to support and propagate bending waves.

Abstract: A new type of diaphragm transducer comprising magnets to provide magnetic field strength in a planar region and a planar diaphragm located in the said planar region. The diaphragm has a plurality of conductors on its planar surface for inducing electromagnetic forces acting on theses conductors in said planar region when current flows through said conductors. The magnets are arranged in magnetic interaction with a magnetically conducting material, preferably soft iron, to conduct magnetic field from said magnets to said planar region.

Abstract: A transparent panel-form loudspeaker consists of a transparent sound radiation panel that can radiate sound with desired pressure level over a specific frequency range when subjected to the flexural vibration induced by a preselected number of transducers located at specific positions on the peripheral edge of the transparent sound radiation panel and a rigid frame carrying a flexible suspension device which supports the periphery of the transparent sound radiation panel. The transparent sound radiation panel is made of a kind of transparent materials with the ratio of elastic modulus to density in the range from 3 to 180 GPa/(g/cm3) and the ratio of length to thickness of the transparent sound radiation panel in the range from 80 to 600.

Abstract: An acoustic device has a suspended sheet of a thin flexible material having a rigid rod secured along one edge. An audio frequency actuator, which is preferably a magnetostrictive actuator, is acoustically coupled to an end face of the rod. The audiofrequency actuator is supplied with an audio signal from an audio source such as player device selected from the group which includes a recording tape player, a CD player, a DVD player, and a solid state memory device.

Abstract: An electrostatic transducer, such as a loudspeaker or microphone, comprises a multi-layer panel (1) incorporating an electrically insulating middle layer (2) sandwiched between first and second electrically conducting outer layers (3, 4). At least one of the layers has a profiled surface (6) where it contacts the surface of another of the layers. Furthermore a signal generator is provided for applying an alternating electrical voltage across the first and second layers (3, 4) to initiate vibration due to variation of the electrostatic forces acting between the layers, thereby serving as a loudspeaker (or for detecting variation of such electrostatic forces due to received vibration in the case of a microphone).

Abstract: A panel form loudspeaker comprises a resonant multi-mode radiator (11) which in turn comprises a plurality of substantially concentric sub-panels (20, 21, 22, 23). A plurality of analogue drivers (10) drive the radiator (11), one or more of the drivers being operational at any time. A signal level measured at the input to the loudspeaker determines the operational state of each of the drivers (10). The concentric sub-panels may take various shapes and have different areas.

Abstract: A door leaf includes a stiff, light structural part that maintains fed-in vibrational energy and, by flexural waves, propagates this energy in at least one active surface perpendicular to its thickness to distribute resonance mode vibration components over at least one surface, which has specified, preferred locations or sites within it for transducer devices, which are affixed on the structural part at one of the locations or sites to set the structural part into vibration and to allow it to resonate, thus creating an acoustic radiator that delivers an acoustic output signal when it vibrates in resonance, the front and/or the rear cover panel of the door leaf being part of the stiff, light structural component. The transducer(s) is/are situated between the cover panels.

Abstract: A speaker apparatus can ensure a large size and area of a diaphragm so as to improve reproducing capability in a low sound range and increase an output sound pressure, and can constitute a plurality of vibrating points (signal control points). An input signal Vin having a plurality of independent channels is inputted, then the signal input Vin is processed in a sound signal processing portion by calculating and adding of an interference canceling signal between the signal control points, by calculating and adding of a sound interference signal for causing the interference between outputs from the signal control points in an arbitrary point, etc., so as to be inputted to transducers that are attached to a single diaphragm. The transducer transduces an electric signal into mechanical vibration. A plurality of the signal control points are generated on the single diaphragm, and each signal control point cause the single diaphragm to vibrate.

Abstract: A method of improving the modal resonance frequency distribution of a panel (2) for a distribution resonant mode bending wave acoustic device involves analysing the distribution of the modal resonance frequencies of the panel, identifying a modal resonance frequency that is non-uniformly spaced relative to adjacent modal resonance frequencies, identifying a location on said panel that exhibits anti-nodal behaviour at said modal resonance frequency and changing the local impedance to bending wave vibration at said location (6). The method has particular application to distributed mode loudspeakers (1).

Abstract: An electroacoustic transducer includes a magnetic circuit of a magnetically conductive material with a pair of opposed surfaces defining a gap therebetween. The magnetic circuit includes a magnet inducing a magnetic field in the gap, the magnet having a surface constituting one of the opposed surfaces. The magnetic circuit further includes a diaphragm and a coil having electrically conducting paths secured to the diaphragm. The coil has portions of its paths situated in the gap.

Abstract: A flat panel loudspeaker arrangement with several panel loudspeakers of similar construction is disclosed. The panel loudspeakers are arranged seamlessly side-by-side and are rigidly connected with one another along their respective edges with a high shear strength. The panel loudspeakers can be supported by an existing stable wall.

Abstract: A structure of a rectangular panel-form loudspeaker is provided. The structure includes a radiating panel, a transducer, a frame and a suspending unit. The radiating panel includes a rectangular laminated composite plate with length b and width a, and the laminated composite plate includes an intermediate core layer sandwiched between two fiber-reinforced polymeric layers. The transducer is used for exciting the radiating panel to produce flexural vibration. The transducer includes a voice coil assembly and a magnet assembly, wherein the voice coil assembly is coupled to a first side of the laminated composite plate at a first specified location. The frame is used for positioning the laminated composite plate and the magnet assembly. The suspending unit is made of a soft material and disposed between peripheral edges of the laminated composite plate and the frame.

Abstract: A loudspeaker comprising a phase uncorrelated diffuse sound source and a duct or wave guide coupled to the sound source to direct acoustic energy from the source, the duct or wave guide having a substantially parallel section extending from the vicinity of the sound source and a termination positioned remotely from the panel.

Abstract: A media window system includes a window unit having a window frame defining a frame perimeter and a glass unit located within the frame perimeter. The window unit includes a display area adapted to receive a display image. A display image source is configured to project an image onto the display surface. The window unit also includes a speaker element disposed on the window. The display are of the window unit is capable of transforming from a first transparent state to a second increased opacity state for receiving the display image.

Abstract: A loudspeaker comprising a resonant panel-form member adapted to produce an acoustic output and a vibration exciting system on the panel-form member and adapted to apply bending wave energy thereto, characterized in that the vibration exciting system is adapted to apply a bending couple to the panel-form member.

Abstract: A touch pad assembly for use in an electronic article. The assembly comprises a touch pad, a coupler for mechanically coupling the touch pad to casing of the electronic article and a transducer which is mounted by coupling means on the coupler or the touch pad to drive the casing as an acoustic radiator. An electronic article can incorporate the same. An electronic article comprises a body in or on which a bending wave loudspeaker is mounted. The loudspeaker comprises a bending wave acoustic radiator and an electromechanical force transducer mounted to the radiator to vibrate the radiator to produce an acoustic output. The transducer has an intended operative frequency range and comprises a resonant element having a frequency distribution of modes in the operative frequency range and coupling means for mounting the transducer to the radiator.

Abstract: Electro-acoustic device which when installed in continuous ceiling, partition or wall panels available in the market made of mineral fibre, plasterboard, multi-laminated wood, etc. converts them into flat, invisible radiators of high-fidelity sound by its special characteristic of being equalizable for each type of panel at the time of manufacture and assembly.

Abstract: Arrangement of a sound reproduction system (1), including at least one input (2), a sound field generator (4), a loudspeaker panel (10); the at least one input (2) connected to the sound field generator (4), and the sound field generator (4) connected to the loudspeaker panel (10); the at least one input (2) arranged for generating an audio signal; the sound field generator (4) including a wave field synthesizer (6) arranged for generating a spatially perceptible sound field for the audio signal and for outputting the spatially perceptible sound field to the loudspeaker panel (10), the loudspeaker panel (10) being a multi-exciter Distributed Mode Loudspeaker panel (10) consisting of a plate (12) and a plurality of transducers (16), arranged within an array (14) on the large plate (12) for reproducing the spatially perceptible sound field from the wave field synthesizer (6) by exciting bending waves in the plate (12).

Abstract: A loudspeaker drive unit comprising a resonant acoustic radiator, an exciter on the radiator to apply bending wave energy to the radiator to cause it to resonate, a support for the loudspeaker drive unit, and means resiliently coupling the exciter to the support.

Abstract: The present invention is directed to a diaphragmatic (planar) electroacoustic transducer that forms a complete sound radiating transducer and provides high efficiency and linearity. The diaphragm is easily exchangeable and rectangular in shape, and may be made of very thin polyamide film with a plurality of aluminum conductors formed on one side of the diaphragm. The plurality of conductors form two identical and symmetrical coils such that conductors of each coil are interlaced. The two sections of the coils are disposed in dense air-gaps of the magnet system, which comprises a plurality of high (BHmax) Neodymium magnets. The binary interlaced coils can be utilized in a number of modes, for the purpose of accomplishing a variety of operating modes.

Abstract: A panel-form loudspeaker includes a radiating panel, a frame, a suspension unit, a transducer and a linkage unit. The frame is used for supporting and positioning the radiating panel. The suspension unit is disposed between the frame and the bottom periphery of the radiating panel, and is made of a soft material. The transducer includes a voice coil unit and a magnet unit. The voice coil unit is coupled to the radiating panel at a specific location under the radiating panel. The linkage unit includes a first linking portion coupled to the frame, a second linking portion coupled to the voice coil unit via a resilience support, and a third linking portion coupled to the magnet unit.

Abstract: Acoustic device including a member extending transversely of its thickness and capable of sustaining bending waves at least over an intendedly consequentially acoustically active area of the transverse extent of said member, the member having, by reason of orderly design methodology disclosed and claimed, a distribution of resonant modes of its natural bending wave vibration at least over said area that is dependent on values of particular parameters of said members, including geometrical configuration and directional bending stiffness(es), which values have been selected to predetermine said distribution of natural resonant modes being consonant with required achievable acoustic action of said member for operation of said device over a desired operative acoustic frequency range.

Abstract: A planar type speaker keeps its diaphragm (2) free from any distortion in operation, thus providing high fidelity sound reproduction. The diaphragm (2) is of a planar type and surrounded by a flexible edge member (3). This member (3) is constructed of an inner edge piece (3a) and an outer edge piece (3b) each of which has a semicircular shape in cross section to provide a convex surface and a concave surface. These edge pieces (3a, 3b) are the same in construction, but are inverted in arrangement to have the concave surfaces thereof face to each other to sandwich the diaphragm (2) between the concave surfaces of the edge pieces (3a, 3b); and, the outer edge piece (3b) is provided with a plurality of notched holes (7) which are symmetrically arranged in the outer edge piece (3b).

Abstract: A vehicle component for mounting in a passenger compartment of a vehicle, the component comprising a loudspeaker having an acoustic radiator capable of supporting bending wave vibration and an electromechanical force transducer mounted to the acoustic radiator to excite bending waves in the acoustic radiator to produce an acoustic output, characterized in that the transducer has an intended operative frequency range and comprises a resonant element having a frequency distribution of modes in the operative frequency range and a coupler on the resonant element for mounting the transducer to the acoustic radiator.

Abstract: The present invention provides an electronic apparatus including a touch pad. The electronic apparatus also includes a housing and a mechanical acoustic transducer. The housing supports an outer circumferential portion of the touch pad via a suspension to provide a space for sound emission between the housing and the touch pad. The electromechanical acoustic transducer is connected to the housing, and emits sound into the space. When the electromechanical acoustic transducer emits the sound into the space, an energy of the sound emitted causes the touch pad to vibrate and thereby to output sound outside the electronic apparatus.

Abstract: A loudspeaker comprising a panel-form acoustic member adapted for operation as a bending wave radiator and an electrodynamic moving coil transducer having a voice coil mounted to the acoustic member to excite bending wave vibration in the acoustic member. The junction between the voice coil and the acoustic member is of sufficient length in relation to the size of the acoustic member to represent a line drive such that the acoustic member has a mechanical impedance which has a rising trend with bending wave frequency.

Abstract: The invention relates to the embodiment of so-called panel loudspeakers working according to the bending wave principle. Said panels are generally formed by a panel (11), at least one driver (12) and a frame (13), the panel (11) being connected to the frame (13). In order to achieve appropriate bending wave induction in the panel (11), very complicated assessments must be made in order to determine the corresponding positioning areas (15) in which the driver (12) excites the panel (11) or is connected to the latter. Furthermore, the size of the panels (11) can change considerably depending on the application so that assessments must only be made repeatedly in the case of panels that can be easily modified. The invention aims at providing general positioning areas (15) for the driver (12) in or on the panels (11) so that no further assessments need to be carried out regarding the positioning area (15).

Abstract: An electro-acoustic transducer (1) is proposed for a component operating with surface waves, in particular for a surface wave filter, in which, to suppress interfering excitation ensuing in the gap region, a variation of the gaps (4) is implemented with regard to at least one feature selected from transversal arrangement, size and shape. Due to the slight dimension change (&Dgr;D) in comparison to the finger length, the desired primary excitation in the transducer remains approximately unchanged, however the interfering excitation is displaced or divided, and therewith made ineffectual.

Abstract: This disclosure is directed to flat panel speakers in which an exciter is mounted at a non-zero angle relative to a flat panel. For example, a mounting bracket can be attached to the flat panel, and the exciter can be mounted on the mounting bracket such that the exciter is rotated at relative to the flat panel. By mounting the exciter at a non-zero angle relative to the flat panel, less surface area of the flat panel is consumed by the presence of the exciter. Accordingly, flat panel speaker designs as described in this disclosure are particularly useful when the surface are of the flat panel is also used for other purposes.

Abstract: A loudspeaker comprising a panel which is sufficiently stiff to support bending waves, the panel having a boundary, a transducer mounted to the panel to apply bending wave energy in the form of dispersive travelling waves thereto at a first location in response to an electrical signal applied to the transducer to cause the panel to vibrate and radiate an acoustic output, the loudspeaker having a frequency range extending from a lower frequency to a higher frequency and the panel having a stiffness giving a coincidence frequency above the lower frequency. Means on or associated with the panel at a second location attenuates travelling bending waves in the panel to prevent or at least substantially to moderate panel resonance.

Abstract: A panel-form loudspeaker includes a radiating panel, a frame, a suspension unit, a transducer and a linkage unit. The frame is used for supporting and positioning the radiating panel. The suspension unit is disposed between the frame and the bottom periphery of the radiating panel, and is made of a soft material. The transducer includes a voice coil unit and a magnet unit. The voice coil unit is coupled to the radiating panel at a specific location under the radiating panel. The linkage unit includes a first linking portion coupled to the frame, a second linking portion coupled to the voice coil unit via a resilience support, and a third linking portion coupled to the magnet unit.

Abstract: A compilation of improvements and modifications to U.S. Pat. No. 5,392,358 which discloses an electrolytic loudspeaker assembly (10) which reproduces a broad band of audio signals. The assembly (10) is comprised of a thin, non-magnetic capacitive transducer (12) which consists of compound diaphragm (14) that is further comprised of a center section (16), a front section (20) and a rear sect compound diaphragm (14) is enclosed by a frame assembly (32). The improvements and modifications to the assembly designs for a center section (16A, 18A); three designs each for a front section (20A, 24A, 28A) and a rear section (22A, 26A, 30A); three designs for a frame assembly (32A, 34A, 36A) and two designs for a transducer driver unit (46, 48). The basic design of the assembly (10) is also augmented by the addition of an acoustic wave diffuser, reflector, and absorbing assembly (40) and an acoustic baffle structure (44).

Abstract: A loudspeaker includes an assembly of at least two bending wave panel-form acoustic members each having a set of modes which are distributed in frequency. The parameters of at least two of the acoustic members are selected so that the modal distributions of each acoustic member are substantially different. The arrangement is such that the modal distributions of the assembly of acoustic members are interleaved constructively in frequency. A transducer applies bending wave energy to the acoustic members to cause them to resonate to produce an acoustic output. A method of making such a loudspeaker is also provided.

Abstract: A speaker apparatus in which the acoustic sound is radiated by flexural oscillations of a diaphragm in the form of a panel having a substantially flat surface. The speaker apparatus includes a panel-shaped diaphragm the outer rim of which can be oscillated substantially freely at least in the direction along the diaphragm thickness and at least one driver unit constituting an oscillation source secured to the diaphragm surface for imparting oscillations to the diaphragm. The diaphragm is set into flexural oscillations by oscillations applied from the driver unit driven on the basis of the playback input signal. By flexurally oscillating the diaphragm to radiate the acoustic sound, optimum frequency response characteristics can be obtained over a wide frequency range from the low to high frequency range. Moreover, the acoustic sound of optimum sound quality may be radiated in a state of minimum sound pressure level fluctuations over a frequency range from the low to high frequency range.

Abstract: An advanced design for an electrostatic and an electrolytic loudspeaker assembly (10) that comprises a compound diaphragm (12) sandwiched between a first metal stator (40) and a second metal stator (60), wherein each stator includes a multiplicity of perforations (41,61). All the sides of the stators (40,60) as well as the inside surface of the perforations (41,61) are coated with an insulating material (90) also known as ACOUSTAGUARD™ (90) which includes a base coat (92) and a sealing and pigmentation coat (94). The coats (92) and (94) are applied by a unique process that allows ACOUSTAGUARD™ to be applied at room temperature by preferably a spraying technique. The application of ACOUSTAGUARD™ avoids any arcing or corona discharge between the two stators (40,60) which can distort the audio output and damage the loudspeaker assembly (10).