Abstract: Provided is a cover for pressing a printed circuit board on a heat sink, the cover comprising a metal sheet and one or more domes arranged in the metal sheet, wherein each dome is associated with one or more slits in the shape of ring segments in the metal sheet, the ring segment-shaped slits being provided in the metal sheet side by side and spaced apart from each other, the ring segment-shaped slits surrounding the dome they are associated with. At least at one end of each ring segment-shaped slit a slit extension may be provided in the metal sheet, the slit extension at least in part pointing away from the dome the ring segment-shaped slit is associated with. Further provided is an electronic appliance that includes such a cover, a heat sink and an electronic circuit board sandwiched there between.

Abstract: A loudspeaker arrangement comprises a transducer arranged in a loudspeaker enclosure, the loudspeaker enclosure enclosing a rear part of the transducer, and an aperture-defining structure (hereinafter, the aperture) mounted on a front side of the transducer in a direction of propagation of sound emitted by the transducer. The transducer is configured to emit sound within a wide frequency range, and at frequencies of above a predetermined threshold. The aperture is configured to amplify sound at predetermined frequencies or within a predetermined frequency range within the wide frequency range, and to let sound at all other frequencies within the wide frequency range pass essentially unaltered. The loudspeaker enclosure is sized such that the resonance frequency of the loudspeaker enclosure matches the resonance frequency of the transducer in free air, wherein the resonance frequency of the transducer in free air is below the predetermined threshold.

Abstract: A loudspeaker comprises a diaphragm, a tubular voice coil assembly coupled to the diaphragm, a magnet assembly providing an annular gap in which the tubular voice coil assembly is arranged, and a flexible suspension. A longitudinal axis of the tubular voice coil assembly extends along a central axis of the loudspeaker. A longitudinal axis of the annular gap extends along the central axis of the loudspeaker. The flexible suspension has a disc shape and is configured to guide a movement of the tubular voice coil assembly along the central axis of the loudspeaker. The flexible suspension extends substantially perpendicular to the central axis. An inner diameter of the tubular voice coil assembly is greater than or equal to an outer diameter of the flexible suspension.

Abstract: In at least one embodiment, a loudspeaker assembly is provided. The loudspeaker assembly includes a supporting ring, a flexible surround, a voice coil, a dome, and a bearing ring. The flexible surround includes a first end being attached to the supporting ring and a second end positioned opposite to the first end. The voice coil is positioned about the flexible surround. The dome is positioned about the voice coil and the second end of the flexible surround. The bearing ring is attached to the voice coil and separates the flexible surround from the dome.

Abstract: Provided is a cover for pressing a printed circuit board on a heat sink, the cover comprising a metal sheet and one or more domes arranged in the metal sheet, wherein each dome is associated with one or more slits in the shape of ring segments in the metal sheet, the ring segment-shaped slits being provided in the metal sheet side by side and spaced apart from each other, the ring segment-shaped slits surrounding the dome they are associated with. At least at one end of each ring segment-shaped slit a slit extension may be provided in the metal sheet, the slit extension at least in part pointing away from the dome the ring segment-shaped slit is associated with. Further provided is an electronic appliance that includes such a cover, a heat sink and an electronic circuit board sandwiched there between.

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: An electro-acoustic transducer has a membrane comprises a folded or curved sheet of film material. A frame supports the membrane in at least an upper end thereof. A resilient suspension connects the upper ends of the membrane to the frame. A driver system is attached to the frame and the membrane for moving the membrane dependent on an electrical input signal. At least one ferromagnetic element is arranged in the membrane or on one of the surfaces of the membrane at its lower end. At least one magnet provides a magnetic field, the magnet being attached to the frame in a position adjacent the lower end of the membrane. The ferromagnetic element is pulled down by a magnetic force between the element and the magnet establishing a gap therebetween such that tensioning of the membrane is achieved by the magnetic force.

Abstract: An electro-acoustic transducer includes a generally V-shaped diaphragm comprising a folded sheet of film material. The diaphragm also comprises two upper ends, a lower end, an inner surface, and an outer surface. A frame supports the diaphragm in at least the two upper ends of the diaphragm and a structured conductive layer is arranged on a surface of the diaphragm. Permanent magnets are attached to the frame adjacent to the upper two ends and the lower end of the diaphragm.

Abstract: A planar loudspeaker includes a shell pot, a magnet, a diaphragm, and a face plate. The magnet may be positioned in a cavity in the shell pot. The diaphragm may be coupled with the shell pot to cover an entrance to the cavity. The shell pot may include a conductive path having an inner contact proximate the central axis of the diaphragm, and an outer contact proximate to a perimeter of the diaphragm. The face plate may be coupled with the shell pot so that the diaphragm is positioned between the magnet and the faceplate. The face plate may include an inner terminal and an outer terminal that are aligned to be in direct contact with the respective inner contact and the outer contact of the diaphragm and form an electrical connection there between when the face plate is coupled with the shell pot. The inner and outer terminals may be coupled with a source of electrical signals, such as an audio amplifier.

Abstract: An electro-acoustic transducer has a membrane comprises a folded or curved sheet of film material. A frame supports the membrane in at least an upper end thereof. A resilient suspension connects the upper ends of the membrane to the frame. A driver system is attached to the frame and the membrane for moving the membrane dependent on an electrical input signal. At least one ferromagnetic element is arranged in the membrane or on one of the surfaces of the membrane at its lower end. At least one magnet provides a magnetic field, the magnet being attached to the frame in a position adjacent the lower end of the membrane. The ferromagnetic element is pulled down by a magnetic force between the element and the magnet establishing a gap therebetween such that tensioning of the membrane is achieved by the magnetic force.

Abstract: The invention relates to an electromagnetic driver comprising a soft magnetic core in the form of an E with three legs and a back, an alternating field driver, magnetically coupled to the soft magnetic core, for generating an alternating magnetic field in the soft magnetic core, depending upon a sound signal, a constant field driver magnetically coupled to the soft magnetic core for generation of a constant magnetic field in the soft magnetic core, a soft magnetic element for coupling to the plate of the planar diaphragm loudspeaker, lying opposite the back and magnetically closing the legs across at least one small induction gap, whereby the constant field and the alternating field are asymmetrically superimposed such that a resulting force, or a resulting torque on the soft magnetic element, is proportional to the sound signal.

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 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: 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 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: The invention relates to an electromagnetic driver comprising a soft magnetic core in the form of an E with three legs and a back, an alternating field driver, magnetically coupled to the soft magnetic core, for generating an alternating magnetic field in the soft magnetic core, depending upon a sound signal, a constant field driver magnetically coupled to the soft magnetic core for generation of a constant magnetic field in the soft magnetic core, a soft magnetic element for coupling to the plate of the planar diaphragm loudspeaker, lying opposite the back and magnetically closing the legs across at least one small induction gap, whereby the constant field and the alternating field are asymmetrically superimposed such that a resulting force, or a resulting torque on the soft magnetic element, is proportional to the sound signal.

Abstract: A planar loudspeaker includes a shell pot, a magnet, a diaphragm, and a face plate. The magnet may be positioned in a cavity in the shell pot. The diaphragm may be coupled with the shell pot to cover an entrance to the cavity. The shell pot may include a conductive path having an inner contact proximate the central axis of the diaphragm, and an outer contact proximate to a perimeter of the diaphragm. The face plate may be coupled with the shell pot so that the diaphragm is positioned between the magnet and the faceplate. The face plate may include an inner terminal and an outer terminal that are aligned to be in direct contact with the respective inner contact and the outer contact of the diaphragm and form an electrical connection there between when the face plate is coupled with the shell pot. The inner and outer terminals may be coupled with a source of electrical signals, such as an audio amplifier.

Abstract: An electro-acoustic transducer includes a generally V-shaped diaphragm comprising a folded sheet of film material. The diaphragm also comprises two upper ends, a lower end, an inner surface, and an outer surface. A frame supports the diaphragm in at least the two upper ends of the diaphragm and a structured conductive layer is arranged on a surface of the diaphragm. Permanent magnets are attached to the frame adjacent to the upper two ends and the lower end of the diaphragm.

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 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.