Abstract: Described is a loudspeaker enclosure arrangement that reduces, by a large degree, internal acoustic reflections, enclosure vibrations, and diffraction off the surfaces and edges of the loudspeaker enclosure. The loudspeaker exterior surfaces and edges are covered with acoustic damping foam. The enclosure is shaped to dissipate sound waves within the enclosure, rather than allowing the sound waves to reflect off its walls. To achieve the objects set forth above, the design comprises a loudspeaker in which the exterior of the side walls are prevented from communicating interfering sound by the placement of exterior sound-damping foam blocks. The design also comprises a loudspeaker enclosure that has a triangular horizontal cross section. Internal sound waves diminish toward the distal point of the enclosure and are not reflected forwardly.

Abstract: The invention relates to the embodiment of panel loudspeakers 10 working according to the bending wave principle. Such loudspeakers 10 generally consist of an acoustic panel 11 and drivers 12, whereby the drivers 12 are connected to the acoustic panel 11. For the formation of bending waves in the acoustic panel 11, it is essentially important that the drivers 12 do not unnecessarily rigidize the acoustic panel 11. This has led to the arrangement of the drivers 12 at a distance from the acoustic panel 11 in a separate frame. In view of the complexity of such an arrangement, the invention aims at providing a connection between the drivers 12 and the acoustic panel 11 that can be supported directly on the acoustic panel 11 and which does not impede the propagation of the bending waves. This is achieved by connecting the drivers to the acoustic panel only at very few points 24 or by providing elastic member 25 in the fixing area of the drivers. A combination of both embodiments is also described.

Abstract: A loudspeaker comprising a bending wave panel, an enclosure in which the bending wave panel is mounted to enclose one face of the panel, a compliant suspension between the panel and the enclosure by which the panel is supported in the enclosure, a vibration exciter attached to the panel to apply bending wave energy thereto, and an acoustic absorber in the enclosure to reduce standing waves in the enclosure, wherein the compliant suspension and the acoustic absorber are integral. A method of making such a loudspeaker is also disclosed.

Abstract: A damping material for use in a loudspeaker enclosure to enhance sonic properties of the enclosure. The material for use in the enclosure is kapok, a fibrous material with a relatively low density. By incorporating the kapok within the enclosure, either standing alone or in combination with other materials known to function as acoustic dampers, the overall result is that the sonic quality of the speaker system is increased and may also be reduced in size without sonic compromise.

Abstract: A speaker apparatus comprises a speaker unit, a cabinet for forming an internal space on the rear side of the speaker unit with a plurality of wall surfaces including a baffle plate for use in mounting the speaker unit, a acoustic tube which is formed along at least one wall surface out of the plurality of wall surfaces and has not only a substantially uniform hollow section but also an opening at one end, and an acoustical material for separating the internal space from the internal space of the acoustic tube by closing the opening of the acoustic tube. The speaker apparatus is characterized in that the acoustic tube has a tube length about 1/(2n) (n=positive integer) time as large as a wavelength corresponding to the lowest resonance mode of the standing wave produced along the one wall surface out of the standing waves produced in the internal space and that the opening is disposed close to the node of the standing wave.

Abstract: A speaker system suppresses standing waves generated in the system and reproduces clear and dynamic bass sound. The system includes a cabinet formed of acoustic isolation walls, and at least one partition wall situated inside the cabinet to form a space by surrounding the space. The partition wall suppresses the standing waves generated inside the cabinet and is formed of a material having high internal loss. The space has a total capacity more than one tenth of a capacity of the cabinet, wherein a closed end of the partition wall is located between one-half and four-fifths of a distance from one end to the other end, and an opening area of the same partition wall is located at a side opposite to the closed end in a longitudinal direction of the cabinet. The opening area is located between four-fifths and five fifths of a distance from one end to the other end.

Abstract: In a device (8) which includes an electroacoustic transducer (7) for the acoustic reproduction of sound signals to an ear (14) of a user (2) who assumes a user position at the device (8), the transducer (7) is optimized for the acoustic reproduction of speech-signal sound waves and is equipped with additional means (25) for realizing a distinct directivity for the speech-signal sound waves emitted by said transducer (7) and, as a result of its directivity, the transducer (7) directs the speech-signal sound waves which it emits preferentially to the ear (14) of a user (2) who is in the user posture.

Abstract: An acoustic waveguide loudspeaker system has an electroacoustical transducer having a vibratile surface. An acoustic waveguide has a first end open and a second end adjacent to the vibratile surface and an effective length corresponding substantially to a quarter wavelength at the lowest frequency of pressure wave energy to be transmitted between the first and second ends. Damping material in the waveguide near the vibratile surface is positioned so as to negligibly attenuate bass frequency energy while of sufficient volume to damp peaks at higher frequencies above the range of the bass frequency energy.

Abstract: A sound muffling and heat-discharging case for a computer storage apparatus includes a casing having an opened upper portion and receiving the storage apparatus therein, a cover having a severed side portion partially exposing the peripheral parts of the storage apparatus and serving as a heat discharging portion and covering an upper portion of the casing, and noise-absorbing member being provided along an inner periphery of each of the casing and the cover and absorbing a noise from the storage apparatus. The sound muffling and heat-discharging case effectively decreases noise and heat occurring from a hard disk drive while simplifying the case structure of and thereby facilitating its fabrication.

Abstract: An apparatus for protecting equipment in an outdoor communication structure from adverse weather conditions, vibration, and vandalism includes a housing that possesses hidden lip door edges and is assembled such that no screws, nuts, hinges, etc. are left exposed. Also, any speakers and/or microphones are largely isolated from potential vibration by surrounding them with vibration dampeners such as foam or other padding or insulation. Heat, dust intake, vibration, and electricity usage are reduced by providing convection venting wherein the internal cavity of the housing narrows at a top region of the housing. Vents in the top region of the housing allow air from the narrowed internal cavity to escape as it heats and expands. As hot air is displaced from the narrowed internal cavity, cooler ambient air is drawn into the internal cavity through bottom vents in a bottom region of the housing.

Abstract: The television having a device for preventing vibration of speaker comprises a speaker. The speaker is fixed on one wall toward a hollow portion formed in an enclosure, and an opening for emitting sound is formed on the enclosure. A vibration plate faces the speaker to be positioned in the opening at a predetermined interval from the speaker. And, a mounting means for mounting the vibration plate on the enclosure is provided. Therefore, vibration of speaker emitting medium/low bandwidth sound outside and vibration of cabinet in which the speaker is mounted is minimized so that quality of sound becomes high and sound having high power is emitted outside.

Abstract: A loudspeaker mounting plate having metal rods embedded in a body in such a way that both rigidity and internal damping are maximized. A circular hole is included to allow for the mounting of a loudspeaker. Two sets of metal rods are utilized, the first being placed partially under the loudspeakers frame for maximum surface hardness, and the second being used for bracing the width of the plate. The use of two materials with different properties results in a structure that is highly resistant to vibration.

Abstract: An improved acoustic horn for loudspeakers is provided. The acoustic horn of the referred embodiment of the present invention includes a one piece body that incorporates damping material within the body. Preferably, the one piece body is slotted and vibration damping material is provided within the slots. The horn is fabricated by casting from suitable metals and metal alloys. In the preferred embodiment, the body comprises four outwardly curved and flared side walls and is generally rectangular. Each wall of a pair of the opposed side walls is cast with a slot. Vibration damping material is provided in each slot to substantially reduce the structural resonances of the one piece body, so that the acoustic horn has enhanced vibration damping. Various vibration damping materials that are flexible relative to the body and have a high loss tangent are used. Suitable materials include hot melt adhesives, epoxy resins, and commercially available elastomeric materials.

Abstract: A kit for assembling modular support structures is described. The kit comprises structural members and joining means. The joining means further comprise straight members, angle members and "T"-shaped members. A variety of different support structures of different shapes and sizes can be assembled by inserting the ends of the structural members into the ends of the various joining means. Furthermore, angle members may be arranged to include wheeled means, allowing for the construction of mobile support structures.

Abstract: An acoustic damping material that includes at least one resilient sheet, wherein each of the sheets have a first side and a second side, and wherein at least two portions of the sides face each other to form a multi-layered structure, is provided. The resilient sheet may be made from any resilient polymer film, such as a polyolefin, and especially polyethylene. Also provided is an acoustic speaker system that has an exceptionally flat frequency response, especially at low audible frequencies. The system includes an enclosure, a speaker mounted to the enclosure, and acoustic damping material (according to this invention) inside the enclosure. An acoustic damping panel, which includes a frame and acoustic damping material fixed to the frame, is also provided.

Abstract: To prevent the generation of audible resonation of the baffle plate by rigid connection of the weighty speaker unit, the speaker system having a cabinet including a speaker unit uses a support structure which allows movement of the speaker unit in its axial direction, and a flexible seal member fitted into a gap formed between the baffle plate of the cabinet and the frame of the speaker unit or a sub-baffle connected to the frame of the speaker unit. In one embodiment, the support structure includes a swingable plate to which the speaker unit is fixed. A clamp device is provided to prevent movement of the movable part during the transportation of the speaker system.

Abstract: Acoustical diffuser apparatus for supporting and enhancing the performance of speakers. A preferred apparatus includes a diffuser panel that has an outwardly facing non-planar diffuser surface and an opening corresponding to each speaker for receiving at least a portion of the corresponding speaker therein. The diffuser panel does not cover the sound emitting surface of at least one speaker. The diffuser panel may have acoustically transparent material affixed thereto. Methods for installing the diffuser panels into existing wall or ceiling structures without compromising the structural integrity of such structures are also disclosed.

Abstract: A portable loudspeaker enclosure is made of a collapsible shell of a fabric material, e.g., canvas, having top, bottom, left, right, and back walls. These walls each are each formed of a sandwich of fabric layers and an acoustic insulation layer, such as foamed plastic or glass fiber, the insulation layer being disposed to the inside of the shell. The fabric at each wall forms a pouch co-extensive with the wall. A rigid speaker frame serves as a front wall for the enclosure and is fitted into the front of the enclosure. The frame extends within the shell towards the back wall to a point behind the loudspeaker, i.e., about one-third of the front-to-back dimension. For each wall there is a rigid batt or insert that is dimensioned to fit removably into the pouch. The batts create a rigid cavity behind the loudspeaker. The portable enclosure can have a front cover that removably covers the front wall of the enclosure, i.e., for storage and transit.

Abstract: A loudspeaker case structure for a video display appliance capable of damping and absorbing vibrations arising from the output of a loudspeaker to remove the howling phenomena produced on a cathode-ray tube by the transfer of the vibrations to the cathode-ray tube. The loudspeaker case structure includes a housing having a predetermined space for receiving the loudspeaker therein, dispersing and damping the vibrations from the loudspeaker through the space, and a supporting section, extending from the housing, for supporting and fixing the housing to a main bracket of a cabinet and absorbing the remaining vibrations passing through the housing.

Abstract: A loudspeaker enclosure having a constrained layer damping system for minimizing the propagation of vibrations and controlling the resonant modes of the enclosure. The enclosure has a front baffle board on which a plurality of transducers are mounted, and a plurality of other walls mounted to the baffle board to form a cabinet structure. The front baffle board comprises an interior substrate, an exterior substrate, and a constrained layer damping material sandwiched between and bonded to the two substrates. The constrained layer damping material comprises an energy absorbing thermoplastic alloy having a very high material loss factor. The other walls of the enclosure also comprise an interior substrate and an exterior substrate with a constrained layer damping material sandwiched therebetween. An extensional damping material may also be bonded to an interior surface of the interior substrates to further control vibrations in the enclosure.

Abstract: A noise-attenuating shielding unit and method for a speaker according to which a shield is formed by a housing of a noise-attenuating material having a metal plate attached thereto. The housing is located over at least a portion of the speaker and relative to the speaker so that the plate is magnetically attracted to the magnet of the speaker to secure the shielding unit to the speaker.

Abstract: An acoustic enclosure system for a loudspeaker includes a vent chamber adjacent to and spanning at least one chamber assembly. A loudspeaker is mounted in each of the chamber assemblies such that the speakers face away from each other when there are more than one speaker. The vent chamber has a port in a side wall that is open to the outside of the enclosure. Each chamber assembly has a port opening to the vent chamber and contains a fluid chamber with a flexible bladder that is filled with fluid and maintained in the chamber assembly a given distance from the corresponding loudspeaker. Each bladder contacts the interior surfaces of the side walls that form the fluid chamber. A flexible support is provided underneath each bladder so that the bladder is substantially maintained a specified distance from the wall supporting the speaker.

Abstract: Shown, in the application, is a novel and extremely cost effective method to replace traditional and contemporary baffles and enclosures used for preventing the cancellation and consequent radiation of lower frequencies from loudspeakers. The space occupied for the added beam element to accomplish this task is smaller than the loudspeaker itself and adds little to the overall size of the loudspeaker system. With this simple element, baffle size, bidirectional, equaphase reproduction down to and including the fundamental loudspeaker resonance, is obtained.

Abstract: A container apparatus including a loudspeaker enclosure means along with a separate compartment means for alternative purposes and means to provide immediate, temporary sound attenuation of enclosure walls around a loudspeaker for ease of transporting whereby a form fitting cushion filled with sound attenuation materials is installed around the enclosure to dampen vibrations due to the firing of the loudspeaker.

Abstract: A speaker propagating sound waves in the manner of a point source. The speaker includes high, medium, and low range drivers vertically arranged within a vertically arranged tubular support member having sound escape openings in its lateral wall. The high and medium range drivers project sound upwardly, and the low range driver projects sound downwardly. The speaker has a truncated obeliskoid housing including a chamber disposed below the low range speaker. This chamber is muffled to absorb non-coherent sound, and has a vertical air tube for managing air flow within the chamber and conducting sound waves downwardly from the housing. The high range driver is exposed above the housing, so that sound projects upwardly therefrom. Sound produced by the medium range driver passes through the openings in the tubular support member. The housing is supported on casters for mobility.

Abstract: A sound radiated from the back of a speaker unit passes through a three-dimensional spiral sound passage formed by a coaxial dual-tube structure of an outer tube and an inner tube, and by a spiral partition plate provided to bridge a gap between the outer tube and the inner tube before exiting the speaker system. The cross-sectional area of the spiral sound passage may continuously expand or remain constant.

Abstract: A speaker system provides good acoustic characteristics for use in visual equipment, by controlling the turbulence in mid-range of response frequency characteristics to be flat so as to produce an excellent speech articulation. This is accomplished by coupling an acoustic pipe to the front of a speaker unit to guide sound waves through an opening of generally rectangle shape. A resonance absorption section is formed by a tube, one end of which forms a hole for absorbing sound facing to a sound path running within the acoustic pipe from the front of speaker unit to an opening, and a cavity having a small gap along the edge, except the area where is coupled through with the other end of tube. By constructing the speaker system in this way, the width of band to be absorbed and the Q of a dip can be controlled to suppress the peaks and dips, thereby providing a speaker system of good acoustic characteristics where the response frequency characteristics are flat and the speech articulation is excellent.

Abstract: A portable computer system including sealed acoustic suspension speaker enclosures which are each molded of a high density-low-density polymer combination, so that the low-density polymer can provide good sealing to adjacent surfaces. Preferably, neither speaker enclosure is sealed as a free standing unit, but the acoustic seal is completed only when the speaker enclosure is in place inside the portable computer.

Abstract: A sound-reproducing apparatus comprises an acoustic horn which terminates in an opening in the wall of the apparatus. An obstacle is arranged in the acoustic duct of the horn, which provides a better frequency response.

Abstract: Attempts to achieve fidelity of sound produced by speaker systems has led to often large, relatively complicated and expensive speaker cabinets, particularly for reproducing sound in the lower acoustic frequencies. A simple solution to the problem is a speaker assembly including a housing divided by a partition into a speaker chamber containing a speaker and a sound outlet chamber. The sound outlet chamber contains a sound outlet box remote from an opening in the partition connecting the speaker chamber to the sound outlet chamber. A sound outlet tube extends through the box and one wall of the housing. The interior of the box and at least a portion of the area around the box are filled with sand or another solid material for eliminating vibration or at least reducing vibration to a minimum.

Abstract: A loudspeaker enclosure having a low reflection/low diffraction baffle for reducing acoustic reflections and diffraction. The baffle of the loudspeaker enclosure has a substantially entire front surface covered by a first layer of optimized acoustical foam for reducing acoustic reflections off of the front surface of the baffle and for reducing diffraction around the edges of the enclosure. A second layer of optimized acoustical foam is secured over the mounting flanges of the transducers, which are mounted to the baffle. The first and second foam layers are formed of a thin sheet casted, polyether urethane foam. A front surface of the first layer of foam is flush with a front surface of the second layer of foam. An interference fit is provided between the first and second layers of foam to prevent any gaps from being formed between the first and second layers. The first layer of foam is thicker than the second layer of foam.

Abstract: An improved system for acoustic enclosures, which greatly enhances sound reproduction, with improved frequency response, reduction in harmonics-induced distortion, improved conversion of electrical to acoustical energy increased purity of sound due to better phase response among its other qualities. The acoustic principles utilized at those of the resonating air column, the horn-type form, and the multiport. A horn-shaped multiport comprised of a number of smaller ports is used to modify the resonating air column to produce the exponential multi-ported acoustic enclosure.

Abstract: A sound imaging system preferably including two enclosures each comprising a truncated conical base unit and a truncated conical upper unit supported above and spaced apart from of the base unit, and containing a bass driver and composite midrange and high frequency drivers. The bass driver is oriented horizontally at the top of the base unit, and the sound energy produced therefrom is reflected by a conically shaped acoustic lens or defector depending from within the interior of the upper unit directly above the bass driver, such that the sound energy is reflected downwardly along and between the spaced apart truncated conical walls of the upper unit and base unit and emanates radially therefrom in all directions. The composite midrange and high frequency drivers are supported at the top of the upper unit on a crown structure having a plurality of vertical legs defining a platform oriented approximately 20.degree. relative to horizontal.

Abstract: An omnidirectional speaker system includes woofer and tweeter speakers mounted in a concave, curved upper housing fabricated of a relatively hard shell exterior and a foam interior, preferably plastic. Beneath the upper housing is a base, including a generally conical phase compensation plug which disperses the sound waves equally in all directions through a circumferential aperture between the upper housing and base. In a preferred embodiment, the cross-sectional shape of the upper housing is parabolic and the cross-sectional shape of the phase compensation plug is hyperbolic. A foam ring is attached to the exterior surface of the upper housing to prevent the formation of a sonic "hot spot" which can lead to a high intensity sonic beam objectionable to listeners.

Abstract: An apparatus and method are disclosed for reducing electromagnetic or acoustic energy scattered in both the near and more generalized vicinity of a source thereof by various phenomena including atmospheric and weather-related effects and diffraction at the top edge of heretofore known barriers. The apparatus includes a member configured for engagement with the top edge of a barrier, with the member having a patterned edge defining a plurality of portions jutting away from the top edge of the barrier and in a direction having a component toward the source, preferably substantially in a more or less horizontal plane with the top edge.

Abstract: A speaker system designed to use wider resonant sound waves by two conventional speakers which are symmetrically and oppositely disposed to face one another along a co-axis on which both axes of the cone paper vibrator of the speakers are aligned. A sponge like sound wave absorbing material with cone-shaped recesses may be disposed in between the speaker and spherical speaker case.

Abstract: A speaker system has a bass-reflex duct provided in a cabinet. A sub-duct is provided on a central portion of the bass-reflex duct. The sub-duct is communicated with the bass-reflex duct, and filled with sound absorbing material for absorbing unnecessary resonance generated in the bass-reflex duct.

Abstract: An audio loudspeaker system is provided which consists of an enclosure having a front wall, a rear wall with a plurality of circular openings, a pair of side wall, a top wall and a bottom wall. A plurality of loudspeaker components are supported on the front wall of the enclosure for radiating sound energy therethrough and having varying frequency ranges. A plurality of tubular ducts are supported in the circular openings in the rear wall and extend inwardly into the enclosure to exhibit a tuned acoustic frequency to the loudspeaker components having the lowest frequency ranges.

Abstract: An omnidirectional speaker system includes woofer and tweeter speakers mounted in a concave, curved upper fabricated of a relatively hard shell exterior and a foam interior, preferably plastic. Beneath the upper housing is a base, including a generally conical phase compensation plug which disperses the sound waves equally in all directions through a circumferential aperture between the upper housing and base. In a preferred embodiment, the cross-sectional shape of the upper housing is parabolic and the cross-sectional shape of the phase compensation plug is hyperbolic.

Abstract: A fluid damped acoustic enclosure system for a loudspeaker is provided. An enclosure defines first and second chambers separated by a common wall in which the loudspeaker is sealably mounted. The first chamber is airtight and the second chamber has a port in a wall thereof communicating with the exterior of the enclosure. A flexible bladder is filled with a fluid and maintained in the first chamber a given distance from the loudspeaker. The bladder receives acoustic pressure waves generated by the loudspeaker. The bladder is further mechanically coupled to a portion of at least one wall of the first chamber that communicates with the exterior of the enclosure.

Abstract: In the speaker system, an acoustic pipe for conducting a sound wave is arranged in front of a speaker for reproducing a middle and low frequency sound. The acoustic pipe has a rectangular open end portion. A speaker for reproducing a high frequency sound is disposed within the acoustic pipe coaxially with and in front of the speaker for reproducing the middle and low frequency. With this construction, attenuation of middle and high frequency components of sound signals which are produced from the middle and low frequency sound reproducing speaker is suppressed. Moreover, it is possible to conduct the high and middle frequency components and a high frequency component, which is reproduced by the high frequency sound reproducing speaker, as naturally composed sound signals to the open end portion of the acoustic pipe. The speaker system thus exhibits excellent characteristics in sound image localization and articulation of sound, thereby providing a high tone quality to the TV.

Abstract: A loudspeaker has a magnetic circuit and a speaker frame attached to the magnetic circuit, which is mounted on a rear tray of an automobile. A grille is attached to the speaker frame so as to reflect sound generated from the magnetic circuit. The grille has a slit so as to radiate the sound in a forward horizontal direction.

Abstract: Lightweight speaker cabinets manufactured from acoustical composite panels having unique acoustical and structural properties, include an acoustical composite laminate consisting of a porous inner core of closed cell rigid urethane foam which is bonded to fiberglass rovings or skin by means of polyester resin and resin tie blocks, interconnecting the exterior and interior roving and core.

Abstract: This mounting assembly (10) for a loudspeaker (30), or similar fixture, includes an enclosure (12) for mounting the loudspeaker (30) to a ceiling (C) or the like. The enclosure (12) includes a wall attached portion (16) having an interior annular flange (20) and an exterior annular flange (22) connected by a peripheral sidewall (24). The loudspeaker flange (32) is attached to the interior flange (20) by removable fasteners (36) and the enclosure is attached to the ceiling by fasteners (40). A baffle (60) is removably attached to the enclosure exterior flange (22) by fixed fasteners (62). The enclosure (12), in one embodiment, includes a fixedly attached closed portion (14) and the enclosure portions are attached to a ceiling (C) by swivel clamping members (50).

Abstract: Disclosed is an improved speaker structure having a rigid unit-support member and a sound-intercepting wall. In order to improve the quality of reproduced sound, the sound-intercepting wall is composed of a layer of sound-absorbent material which is applied at least to outer surface of said unit-support member and a soundproof sheet of an acoustic energy-absorbent material which covers up tightly the layer of sound-absorbent material.

Abstract: In an audio speaker system and speaker-cabinet combination, a speaker positioned in a cabinet is mounted to the cabinet by a mounting assembly made of non-resonant material and clamping a flange of the speaker so as to prevent contact of the speaker with the cabinet wall, and at the same time flush with the front panel of the cabinet. The cabinet is substantially non-resonant and may be made of plywood or plastic.

Abstract: The invention is a low frequency ported loudspeaker system comprising a hollow rectangular enclosure, the enclosure having a woofer driver airtight mounted to an aperature of the enclosure, changes in air pressure of the invention's enclosure's interior air mass are reduced by the coaction of a liquid mass contained within an open-ended manometer type structure, inlet of open-ended manometer type structure being attached to the enclosure and is in pressure conveyance with the invention's interior air mass.

Abstract: A loudspeaker cabinet which is formulated from a nonfoamed, molded, filled polymer having between 20-90% inert filler and a density of between 1.0-6.0 gm/cm.sup.3. Preferably the polymer is a polyester.

Abstract: A portable loudspeaker system that includes loudspeaker means for reproducing relatively high audio frequencies, and amplifier means, and further includes a carrying case formed as a relatively rigid, low-density, releasably matable pair of polystyrene shells that define an enclosed interior space when mated. Mounted in an opening through a wall of one of the shells is a woofer for reproducing only relatively low audio frequencies as acoustic waves radiating away from said case. Disposed within the case is a body of sound absorbing polyurethane foam that has a plurality of relatively large voids for respectively storing the loudspeaker means, the amplifier means and an optional sound source such as a compact disc player.

Abstract: An acoustically shielded speaker enclosure for use in the ear pockets of motorcycle helmets is disclosed wherein parasitic sound waves emitted from the rear side of an enclosed audio loudspeaker are prevented from entering the motorcycle rider's ear and from mixing with and distorting the primary sound waves issued from the audio loudspeaker directed at the rider's ear. The acoustically shielded speaker enclosure consists of a pair of joined together cup-shaped housing assemblies forming a shortened cylinder adapted to enclose and secure an audio loudspeaker, the enclosure having openings in one face of the housing assemblies to allow passage of the primary sound waves from the contained loudspeaker. An acoustic shield attached to the speaker enclosure cylindrical side extends to the edge of the ear pocket and is sealed there.