Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, and a frame. The loudspeaker is for use with an ear of a user being located at a listening position that is in front of the first radiating surface and is 40 cm or less from the first radiating surface.

Abstract: A loudspeaker comprising: a mounting frame; an acoustic radiator; a drive unit. The drive unit includes: a magnet assembly including a magnet unit configured to provide a magnetic field in an air gap, wherein the air gap extends around a movement axis of the inertial exciter; a coil assembly, and a drive unit suspension. The coil assembly includes: an attachment portion which provides an attachment between the coil assembly and the acoustic radiator; a voice coil; a voice coil former which extends from the attachment portion into the air gap, wherein the voice coil is mounted to the voice coil former so the voice coil sits in the air gap when the drive unit is at rest; a tubular member, which is positioned radially outwardly of the voice coil former with respect to the movement axis, and which overlaps the voice coil former along a portion of the movement axis.

Abstract: There is provided a headrest housing a dipole loudspeaker for producing sound at bass frequencies in a forward direction and in a rear direction, a response 180 degrees out of phase from respective front and rear resonating surfaces. The headrest includes a waveguide formation to isolate sound from travelling through the headrest between the front surface and the rear surface. The headrest also includes an attachment formation, and the attachment formation suspends the first frame of the dipole loudspeaker and acts as a secondary suspension system. By including waveguide formations, the sound from the front surface of the dipole speaker can be guided outside of the headrest, wherein the shortest path from the front surface to the back surface is extended to be around the outside of the headrest. Guiding the sound path to be external to the headrest, prevents internal sound guiding compressing the intended path length.

Abstract: A loudspeaker assembly is disclosed that includes a headrest having a front face and a rear face; a bass dipole loudspeaker mounted to the headrest, wherein the loudspeaker includes a diaphragm having first and second radiating surfaces, wherein the radiating surfaces are located on opposite faces of the diaphragm, wherein the diaphragm moves at bass frequencies such that the radiating surfaces produce sound; a bass waveguide to guide bass produced by the first radiating surface via a forward-facing opening provided by the waveguide, wherein the loudspeaker is mounted such that bass produced by the second radiating surface propagates out from the rear face and such that the first radiating surface is closer to the rear face than to the front face. The forward-facing opening is larger than the first radiating surface as projected onto a plane perpendicular to a movement axis of the loudspeaker.

Abstract: A loudspeaker including: a diaphragm having a first radiating surface and a second radiating surface, wherein the first radiating surface and the second radiating surface are located on opposite faces of the diaphragm; a drive unit configured to move the diaphragm based on an electrical signal; a loudspeaker support structure, wherein the diaphragm is suspended from the loudspeaker support structure via one or more loudspeaker suspension elements. The loudspeaker support structure comprises a self-supporting porous shell which encloses a volume configured to receive sound produced by the second radiating surface, wherein at least part of the self-supporting porous shell is provided by at least one self-supporting portion of porous material having a specific airflow resistance in the range 500-10000 Pa·s/m so as to allow sound produced by the second radiating surface to exit the volume enclosed by the shell.

Abstract: A shaker for transmitting vibrations to an application has a frame; magnet unit that provides a magnetic field in a gap; coil assembly including a voice coil mounted to a former. The former is attached to the frame at a former attachment surface and configured to position the coil in the gap, when the shaker is at rest. The magnet unit moves relative to the coil along an axis when the shaker is activated by supplying current to the coil. The magnet unit is suspended from the frame by a suspension arrangement including proximal and distal suspensions which interconnect the frame and magnet unit. The proximal suspension is closer to the former attachment surface than the distal suspension when the shaker is at rest. One of the proximal and distal suspensions has a stiffness K1, and the other K2, wherein K2>K1, and the ratio K1/K2 is 0.4 or less.

Abstract: A loudspeaker for producing sound at bass frequencies including: a diaphragm; a frame, wherein a proximal end of the diaphragm is suspended from the frame by at least one proximal suspension element, wherein the at least one proximal suspension element is configured to substantially prevent translational movement of the proximal end of the diaphragm relative to the frame, whilst permitting translational movement of a distal end of the diaphragm which is opposite to the proximal end of the diaphragm; a drive unit configured to move the distal end of the diaphragm based on an electrical signal.

Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, and a frame. The loudspeaker is for use with an ear of a user being located at a listening position that is in front of the first radiating surface and is 40 cm or less from the first radiating surface.

Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, wherein the first radiating surface and the second radiating surface are located on opposite faces of the diaphragm; a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, wherein the sound produced by the first radiating surface is in antiphase with sound produced by the second radiating surface; a frame, wherein the diaphragm is suspended from the frame via one or more suspension elements, wherein the frame is configured to allow sound produced by the first radiating surface to propagate out from a first side of the dipole loudspeaker and to allow sound produced by the second radiating surface to propagate out from a second side of the dipole loudspeaker.

Abstract: An audible vehicle warning system is arranged for generating a horn signal and includes a loudspeaker system having a loudspeaker arranged for outputting sound signals at least in a selected frequency range comprising at least frequencies from 400 to 2 kHz, a sound library including one or more sound signals intended as a horn signal when output by the loudspeaker. Each of the sound signals has a ? octave frequency band, which is taken as a reference frequency band. The reference frequency band contains at least a predetermined part of the total power of the sound signal. An ? octave frequency band averaged response of the loudspeaker system has in a ? octave frequency band corresponding to the reference frequency band an amplitude level, which is at least a given amount of dB above the average amplitude level in the selected frequency range.

Abstract: A dipole loudspeaker assembly for producing sound at bass frequencies is provided. The dipole loudspeaker can include a diaphragm having a first radiating surface and a second radiating surface located on opposite faces of the diaphragm. The dipole loudspeaker includes a drive unit, wherein the sound produced by the first radiating surface is in anti-phase with sound produced by the second radiating surface. The diaphragm is suspended from the drive unit frame via at least one drive unit suspension. The dipole loudspeaker includes a mounting frame suspension, at least partially overlaps with one or more elements selected from the diaphragm and at least one drive unit suspension as projected onto the same plane, and is formed in a gap between the drive unit frame and the mounting frame and extends substantially continuously around the drive unit frame.

Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, and a frame. The loudspeaker is for use with an ear of a user being located at a listening position that is in front of the first radiating surface and is 40 cm or less from the first radiating surface.

Abstract: A loudspeaker comprising: a mounting frame; an acoustic radiator; a drive unit. The drive unit includes: a magnet assembly including a magnet unit configured to provide a magnetic field in an air gap, wherein the air gap extends around a movement axis of the inertial exciter; a coil assembly, and a drive unit suspension. The coil assembly includes: an attachment portion which provides an attachment between the coil assembly and the acoustic radiator; a voice coil; a voice coil former which extends from the attachment portion into the air gap, wherein the voice coil is mounted to the voice coil former so the voice coil sits in the air gap when the drive unit is at rest; a tubular member, which is positioned radially outwardly of the voice coil former with respect to the movement axis, and which overlaps the voice coil former along a portion of the movement axis.

Abstract: There is provided a headrest housing a dipole loudspeaker for producing sound at bass frequencies in a forward direction and in a rear direction, a response 180 degrees out of phase from respective front and rear resonating surfaces. The headrest includes a waveguide formation to isolate sound from travelling through the headrest between the front surface and the rear surface. The headrest also includes an attachment formation, and the attachment formation suspends the first frame of the dipole loudspeaker and acts as a secondary suspension system. By including waveguide formations, the sound from the front surface of the dipole speaker can be guided outside of the headrest, wherein the shortest path from the front surface to the back surface is extended to be around the outside of the headrest. Guiding the sound path to be external to the headrest, prevents internal sound guiding compressing the intended path length.

Abstract: A loudspeaker includes: a non-perforated membrane having a front surface facing in a forward direction for producing sound to be radiated outwardly from the loudspeaker in the forward direction and a back surface facing in a backward direction opposite to the forward direction, a magnet unit configured to provide a magnetic field in a predetermined region of space, a voice coil rigidly connected to the membrane, and configured to produce in use a magnetic field which interacts with the magnetic field provided by the magnet unit in the predetermined region of space so as to move the membrane along a longitudinal axis of the loudspeaker, a lead wire configured to input a signal to the voice coil. The lead wire is guided to the voice coil via one or more deformed holders. The lead wire remains at a single surface of the membrane without perforating the latter.

Abstract: A loudspeaker unit for producing sound at bass frequencies an array of two or more diaphragms. The first radiating surface and the second radiating surface are located on opposite faces of the diaphragm, and one or more of the diaphragms are included in a first subset of the diaphragms and one or more of the diaphragms are included in a second subset of the diaphragms; a plurality of drive units.

Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, and a frame. The loudspeaker is for use with an ear of a user being located at a listening position that is in front of the first radiating surface and is 40 cm or less from the first radiating surface.

Abstract: An inertial exciter for use with an acoustic radiator, the inertial exciter comprising: a magnet assembly including a magnet unit configured to provide a magnetic field in an air gap, wherein the air gap extends around a movement axis of the inertial exciter; a coil assembly including: an attachment portion configured to provide an attachment between the coil assembly and the acoustic radiator; a voice coil; a voice coil former which extends from the attachment portion into the air gap.

Abstract: A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, wherein the first radiating surface and the second radiating surface are located on opposite faces of the diaphragm; a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, wherein the sound produced by the first radiating surface is in antiphase with sound produced by the second radiating surface; a frame, wherein the diaphragm is suspended from the frame via one or more suspension elements, wherein the frame is configured to allow sound produced by the first radiating surface to propagate out from a first side of the dipole loudspeaker and to allow sound produced by the second radiating surface to propagate out from a second side of the dipole loudspeaker.

Abstract: A loudspeaker for producing sound at bass frequencies including: a diaphragm; a frame, wherein a proximal end of the diaphragm is suspended from the frame by at least one proximal suspension element, wherein the at least one proximal suspension element is configured to substantially prevent translational movement of the proximal end of the diaphragm relative to the frame, whilst permitting translational movement of a distal end of the diaphragm which is opposite to the proximal end of the diaphragm; a drive unit configured to move the distal end of the diaphragm based on an electrical signal.