Abstract: Loudspeaker enclosures that support improved acoustic radiation efficiency at low audible frequencies without compromising acoustic radiation efficiency at mid and high audible frequencies. Embodiments include enclosures having a primary chamber and a secondary chamber acoustically coupled to the primary chamber via a passive radiator. The geometrical characteristics of the secondary chamber and the corresponding air plenum are tailored for enhanced efficiency at low frequencies.

Abstract: An acoustic device comprises a first closed cavity and a second closed cavity, at least a portion of a partition part flexibly deforms, the first closed cavity is adjacent to a vibration diaphragm, and the second closed cavity is far away from the vibration diaphragm; when the vibration diaphragm vibrates, the internal sound pressure of the first closed cavity changes, a flexible deformation part of the partition part deforms with the change, to flexibly adjust the volume of the first closed cavity; the second closed cavity encloses sound waves into the second closed cavity; and the Young's modulus or strength of at least partial region of the flexible deformation part is less than that of the wall of the first and/or the second closed cavity, the Young's modulus of entire region or partial region of the flexible deformation part is less than or equal to 8000 Mpa.

Abstract: A loudspeaker system (700 or 800) and method for tuning ported loudspeakers and reducing unwanted acoustic resonances provides reduced port noise, eliminates undesired port resonances and improves the accuracy and fidelity of reproduced sound in a loudspeaker system of relatively high efficiency with an enclosure including an Eigen Tone Filter structure (“ETF”) comprising a pipe or set of pipes 720, 820 placed inside a loudspeaker vent to absorb the “open pipe” acoustic resonance of the vent. The open-pipe resonance is unwanted and interferes with the midrange performance of the loudspeaker, when in use, if not corrected.

Abstract: A sound bar having a mounting assembly configured to pivotally secure the bar. The sound bar includes an elongated, at least partially hollow, housing. The housing has a body extending between two opposing ends. A speaker array is positioned in the body. At least one speaker is positioned in at least one end of the bar. The end speaker(s) are preferably bass speakers in fluid communication with the hollow housing. A grill is preferably positioned over at least one of the housing ends. The grill preferably has a center hub affixed to an outer rim by spokes defining open spaces in the grill to facilitate the emission of sound. A mount is attached to the sound bar to secure the bar to a structure while allowing the bar to pivot along its longitudinal axis. Preferably, the mount is secured to the center hub of the grill.

Abstract: A loudspeaker system (700 or 800) and method for tuning ported loudspeakers and reducing unwanted acoustic resonances provides reduced port noise, eliminates undesired port resonances and improves the accuracy and fidelity of reproduced sound in a loudspeaker system of relatively high efficiency with an enclosure including an Eigen Tone Filter structure (“ETF”) comprising a pipe or set of pipes 720, 820 placed inside a loudspeaker vent to absorb the “open pipe” acoustic resonance of the vent. The open-pipe resonance is unwanted and interferes with the midrange performance of the loudspeaker, when in use, if not corrected.

Abstract: An acoustic device includes a first sound producing component and a back cavity structure. The first sound producing component has a first front side and a first back side, wherein the first sound producing component is a high frequency sound unit, and the first front side faces a sound propagating opening of the acoustic device. The back cavity structure is connected to the first back side of the first sound producing component. The first sound producing component produces a first acoustic wave from the first front side towards the sound propagating opening, and the first sound producing component produces a second acoustic wave from the first back side towards a back cavity of the back cavity structure. The back cavity structure is configured to flatten a peak or a dip of a frequency response of the first sound producing component.

Abstract: A loudspeaker is provided. The loudspeaker includes an enclosure including an opening, a driver, disposed at the opening in the enclosure, which is configured to be electrically driven. and a constrained acoustic modulator (CAM), disposed at the enclosure, which is not configured to be electrically driven. The CAM is configured to tune the enclosure without the CAM substantially radiating audible sound.

Abstract: The present invention relates to a vehicle door, which is installed on the vehicle. The door includes a shutter, a speaker and an inverted tube. The shutter has an accommodation cavity, and the speaker is installed in the shutter. The inverted tube is located in the accommodation cavity, with one end connected with the interior of the vehicle, and the other end forming an acoustic port with a flange. The inverted tube exports the sound from the rear cavity into the car. The inverted tube with the acoustic port can strengthen the resonance effect of the air, and strengthen the sound wave. It can improve the loudness of the speaker, reduce the noise of the airflow, and effectively improve the sound quality of the speaker.

Abstract: A speaker disposition structure of a vehicle comprises a left hinge pillar and a right hinge pillar both extending in a vehicle up-down direction; a speaker box fixed to a lower portion of one of the left and right hinge pillars, and the speaker box having a closed inner space; and a partition located on a vehicle width direction inner side of the speaker box. A port opening connects with the inner space of the speaker box and is located in a front face of the speaker box. A space portion is surrounded by the front face of the speaker box, the dash panel, the hinge pillar, and the partition. The space portion connects with an occupant space of the space portion. A length of the space portion, from the port opening in a front-rear direction of the vehicle, is greater than a maximum length of the port opening.

Abstract: A sound bar having a mounting assembly configured to pivotally secure the bar. The sound bar includes an elongated, at least partially hollow, housing. The housing has a body extending between two opposing ends. A speaker array is positioned in the body. At least one speaker is positioned in at least one end of the bar. The end speaker(s) are preferably bass speakers in fluid communication with the hollow housing. A grill is preferably positioned over at least one of the housing ends. The grill preferably has a center hub affixed to an outer rim by spokes defining open spaces in the grill to facilitate the emission of sound. A mount is attached to the sound bar to secure the bar to a structure while allowing the bar to pivot along its longitudinal axis. Preferably, the mount is secured to the center hub of the grill.

Abstract: A loudspeaker includes an enclosure having an open front side defining a forward direction for projecting sound, a first support surface configured to support the loudspeaker in a monitor orientation, and a second support surface configured to support the loudspeaker in an upright orientation. In the monitor orientation, the forward direction is arranged at an oblique upward angle relative to a surface on which the enclosure is placed. The loudspeaker also includes an audio transducer positioned within the enclosure and configured to emit sound from the open front side of the enclosure, and a baffle securing the audio transducer to the enclosure. The baffle has a front surface facing in the forward direction and a channel formed in the front surface. The channel is configured to direct water out of the enclosure in the monitor orientation.

Abstract: An electromechanical transducer (e.g., 200 or 300) includes a motor structure and voice coil winding support structure or former (203 or 303) configured with a vented annular spacer (e.g., 250) and vented distal pole tip member (e.g., 255) having aligned radial channels aimed to transport heat away from a voice coil (202 or 302) during the transducer's reciprocating movement while providing an extended, linear dynamic range and continuous cooling for the voice coil. A dual magnetic gap embodiment has an inside annular spacer member (e.g., 355A) and a co-planar outside annular spacer member (e.g., 350-O), each made of a thermally conductive steel alloy.

Abstract: An electroacoustic transducer includes a housing, one or more partition walls, a diaphragm, and a tube. The one or more partition walls divide an inner space of the housing into a plurality of spaces, such that a volume of a first of the plurality of spaces is different from a volume of a second of the plurality of spaces except the first of the plurality of spaces. The diaphragm is disposed in the housing, such that one surface thereof faces the plurality of spaces. The tube establishes communication between a sound wave emission opening that is open to an outer space of the housing and each of the plurality of spaces.

Abstract: A speaker device includes: a speaker unit configured to output a sound; a speaker box covering at least a part of a back surface of the speaker unit; and a duct comprising a first opening that is open within the speaker box, and a second opening opposite the first opening, the duct communicating together an interior and exterior of the speaker box via the first and second openings, wherein the duct further comprises a third opening disposed in a midway location between the first and second openings.

Abstract: A loudspeaker is provided that includes an outer tubular section, an inner tubular section at least partially disposed within the outer tubular section, a driver disposed in the inner tubular section, a sound deflector disposed at a first end of the outer tubular section, and a void defined collectively by a space between a first end of the inner tubular section within the outer tubular section and the sound deflector, and a space between an outer portion of the inner tubular section and an inner portion of the outer tubular section. The sound produced by the driver passes through the void via the space between the first end of the inner tubular section within the outer tubular section and the sound deflector, and then via the space between the outer portion of the inner tubular section and the inner portion of the outer tubular section.

Abstract: Provided is a speaker device, including: a speaker unit; and a speaker cabinet to which the speaker unit is mounted. The speaker cabinet includes an outer plate; and a partition plate arranged between the outer plate and the speaker unit so as to be opposed to the outer plate. The outer plate and the partition plate form a bass reflex port communicating with a rear space of the speaker unit, and the partition plate includes a leading end surface inclined so as to gradually increase a distance from the outer plate as extending forward.

Abstract: The implementations describe a method and a system to perform the method to reduce buzzing in a speaker by obtaining a signal having an audio content, determining a first value of spectral density of the audio content at a first resonance frequency, the first resonance frequency associated with a mechanical motion of at least one member of a speaker assembly, determining a second value of spectral density of the audio content at a second resonance frequency, the second resonance frequency associated with a port of the speaker assembly, determining, responsive to the first value and the second value, that the signal is to produce buzzing of the speaker at the second resonance frequency, producing a modified signal by limiting spectral density of the audio content at the first resonance frequency, and providing the modified signal to the speaker.

Abstract: One embodiment provides a waveguide for controlling sound directivity of high frequency sound waves generated by a speaker driver. The waveguide is positioned in front of the speaker driver. The waveguide comprises one or more ridge areas, one or more recess areas, and one or more smooth surfaces. Each smooth surface connects a ridge area to a recess area to create a smooth transition between the ridge area and the recess area without any seams or sharp transitions. The waveguide shapes propagation of the sound waves to provide a smooth off-axis frequency response for the sound waves.

Abstract: The systems and methods described herein relate to, among other things, a transducer capable of producing acoustic and tactile stimulation. The transducer includes a rigid mass element disposed on the diaphragm of a speaker. The mass element may optionally be removable and may have a mass selected such that the resonant frequency of the transducer falls within the range of frequencies present in an input electrical audio signal. The systems and methods advantageously benefits from both the fidelity and audio performance of a full-range speaker while simultaneously producing high-fidelity, adjustable and palpable haptic vibrations.

Abstract: A speaker system broadly comprises a plurality of speaker assemblies each including a speaker housing, an input circuit, a low range speaker, and a higher-range speaker. The input circuit receives audio signals from a sound system or other controller and actively or passively sends the audio signals to the speakers. The low-range speaker is positioned in the upper section and the higher-range speaker is positioned in the lower section. Each speaker assembly is configured to be spaced from the other speaker assemblies within a listening area with each speaker assembly generating low frequency soundwaves and higher-frequency soundwaves. This reduces or eliminates out-of-phase crossover frequency wave cancellation effects within the listening area. The speaker housings are compact while allowing the low-range speaker and higher-range speaker to effectively produce and project desired soundwaves from the suspended speaker housing into the listening area.

Abstract: The present disclosure provides a speaker, including a first housing having a receiving space, a speaker unit received in the receiving space and provided with a diaphragm configured to vibrate and emit sound, a second housing spaced apart from the first housing, and a connecting member communicating the second housing with the first housing. The diaphragm divides the receiving space into a front acoustic cavity and a rear acoustic cavity, and the diaphragm is spaced apart from the first housing that faces right the diaphragm so as to form the front acoustic cavity. The second housing has an auxiliary acoustic cavity, and the connecting member communicates the auxiliary acoustic cavity with the rear acoustic cavity. The speaker improves a low-frequency performance of the speaker; the electronic apparatus adopting the speaker can utilize an internal unoccupied space as the auxiliary acoustic cavity, thereby improving the low-frequency performance of the electronic apparatus.

Abstract: A loudspeaker is provided that includes an outer tubular section, an inner tubular section at least partially disposed within the outer tubular section, a driver disposed in the inner tubular section, a sound deflector disposed at a first end of the outer tubular section, and a void defined collectively by a space between a first end of the inner tubular section within the outer tubular section and the sound deflector, and a space between an outer portion of the inner tubular section and an inner portion of the outer tubular section. The sound produced by the driver passes through the void via the space between the first end of the inner tubular section within the outer tubular section and the sound deflector, and then via the space between the outer portion of the inner tubular section and the inner portion of the outer tubular section.

Abstract: A bass reflex port including: a tubular body portion; and a surface forming portion which is board-like, and continuous to an inner wall of the tubular body portion and which has a surface extending radially outwardly from an opening end of the tubular body portion disposed in a housing of a speaker, wherein the surface forming portion extends linearly in a direction away from a tube axis of the tubular body portion in a cross section parallel to the tube axis.

Abstract: A speaker system broadly comprises a plurality of speaker assemblies each including a speaker housing, an input circuit, a low range speaker, and a higher-range speaker. The input circuit receives audio signals from a sound system or other controller and actively or passively sends the audio signals to the speakers. The low-range speaker is positioned in the upper section and the higher-range speaker is positioned in the lower section. Each speaker assembly is configured to be spaced from the other speaker assemblies within a listening area with each speaker assembly generating low frequency soundwaves and higher-frequency soundwaves. This reduces or eliminates out-of-phase crossover frequency wave cancellation effects within the listening area. The speaker housings are compact while allowing the low-range speaker and higher-range speaker to effectively produce and project desired soundwaves from the suspended speaker housing into the listening area.

Abstract: A speaker includes a speaker enclosure. The speaker enclosure includes an inner region arranged in a center of the speaker enclosure and an outer region, which surrounds the inner region and includes a plurality of channels connecting the inner region to an environment in which the speaker enclosure is arranged. The speaker also includes a sound transducer arranged in the inner region in the center of the speaker enclosure. Sound produced by the sound transducer radiates through the plurality of channels into the environment. A length of each of the plurality of channels is greater than a length from the center of the speaker enclosure to the environment.

Abstract: A sound emitting device includes: a speaker that is provided at a back surface of a user interface device; a support body that supports the user interface device; a horn portion that is provided in the support body; and a space portion that is a space formed inside the support body and extending from a sound emission region of the speaker to the horn portion.

Abstract: Disclosed herein is the structure of a microspeaker. The structure of the microspeaker includes: a frame configured to have an internal space, a magnetic field part disposed inside the frame and configured to form an air gap along with the frame, and a diaphragm configured to vibrate vertically in response to the operation of a voice coil located inside the air gap. A duct configured to guide an air flow is formed in the circumferential direction of the frame. At least one frame hole is formed such that air enters the duct from the internal chamber of the frame. At least one duct sound outlet is formed such that air having entered the duct is discharged to the outside through the guide path of the duct.

Abstract: A speaker system includes: a speaker unit; a phase-inversion enclosure in which the speaker unit is installed; a bass reflex port that is installed in the phase-inversion enclosure, the bass reflex port having a tubular shape and having an opening, the bass reflex port extending in a first axial direction which is a direction from the opening towards an inside of the bass reflex port, at least a portion of a cross-section of the bass reflex port perpendicular to the first axial direction becoming gradually smaller as going in the first axial direction, and a length of the cross-section in a second axial direction parallel to the cross-section being constant along the first axial direction; and a first flow-regulating plate that is provided near the opening, the first flow-regulating plate having a shape adapted to a flow rate of airflow discharged from the opening or drawn into the opening.

Abstract: A tunable bass reflex ceiling mounted speaker system and a method for tuning same is disclosed. In accordance with at least one embodiment, a speaker system is provided that includes a port tube and a transducer assembly within the interior volume of a back box. The transducer assembly generates a reflexive airwave within the interior volume of the back box. The reflexive airwave moves into and out of the interior volume through the port tube to create a better broadcast sound in a room. The port tube length has a fixed port and an adjustable port that is tunable by an adjustment mechanism.

Abstract: A loudspeaker arrangement in a motor vehicle includes a collision sensor transmitting a collision signal in response to detecting that the motor vehicle has been in a collision. An audio system transmits an audio signal. A loudspeaker includes an air bag connected thereto. The loudspeaker is coupled to the audio system and produces audible sounds based on the audio signal. The air bag is coupled to the collision sensor and is activated in response to the collision sensor transmitting the collision signal.

Abstract: An acoustic device with an open audio device structure that is configured to be carried on the head or upper torso of a user, a housing carried by the open audio device structure, the housing having opposed first and second ends, a flat diaphragm in the housing and comprising a front face and a rear face, the diaphragm configured to radiate front acoustic radiation from its front face and rear acoustic radiation from its rear face, wherein the front and rear acoustic radiations are out of phase, structure that supports the diaphragm such that the diaphragm can move relative to the housing, a primary magnet adjacent to the rear face of the diaphragm, a magnetic circuit that defines a path for magnetic flux of the primary magnet, a voice coil that is exposed to the magnetic flux and is configured to move the diaphragm up and down along a radiation axis that is normal to the front face of the diaphragm, and first and second sound-emitting outlets in the housing, wherein the first sound-emitting outlet is in or p

Abstract: A sound producing apparatus is provided. The sound producing apparatus comprises a driving circuit, comprising a pulse amplitude modulation (PAM) module, configured to generate an driving signal according to an audio input signal, wherein the driving signal comprises a pulse amplitude modulated signal generated according to the audio input signal, the pulse amplitude modulated signal comprises a plurality of pulses at a pulse rate, two consecutive pulses among the plurality of pulses are temporally spaced by a pulse cycle, the pulse rate is a reciprocal of the pulse cycle, and the pulse rate is larger than a maximum audible frequency; and a sound producing device, coupled to the driving circuit, configured to produce sound according to the driving signal.

Abstract: A speaker system for a mobile object capable of being easily mounted on the mobile object is provided. The speaker system includes a speaker unit, enclosure accommodating the speaker unit, and a tubular member one end of which is connected to an internal space of the enclosure, and the speaker unit and the enclosure are built in a back door thereof. A free space in a vehicle is utilized effectively, thereby mounting the speaker system for the mobile object in the vehicle easily.

Abstract: A loudspeaker is provided that includes an outer tubular section, an inner tubular section at least partially disposed concentrically within outer tubular section, a driver disposed in the inner tubular section, a sound deflector disposed at a first end of the outer tubular section, and a void defined collectively by a space between a first end of the inner tubular section within the outer tubular section and the sound deflector, and a space between an outer portion of the inner tubular section and an inner portion of the outer tubular section. The sound produced by the driver passes through the void via the space between a first end of the inner tubular section within the outer tubular section and the sound deflector, and then via the space between an outer portion of the inner tubular section and an inner portion of the outer tubular section.

Abstract: A novel phantom-powered inline preamplifier is configured to provide selective processing of a sound source signal by intelligently determining the need for a low or high impedance matching and transformer coupling, based on high fidelity requirements of a particular sound source signal. For example, the phantom-powered inline preamplifier can intelligently detect a microphone-originating sound source signal and automatically route the microphone-originating sound source signal to a low impedance matching circuit pathway that leads to a phantom-powered output terminal for an optimal hi-fidelity processing specific to the microphone-originating sound source signal.

Abstract: A parabolic-shaped receptacle is provided. The parabolic-shaped receptacle has a frame having a left side that has a left parabolic curvature and a right side that has a right parabolic curvature. Further, the parabolic-shaped receptacle has one or more speaker ports. In addition, the parabolic-shaped receptacle has a coupling mechanism that couples a computing device to the frame such that one or more speakers of the computing device are aligned with the one or more speaker ports to deliver audio from the one or more speakers through the one or more speaker ports. The parabolic-shaped receptacle also has a left receptacle speaker positioned on the frame along the left parabolic curvature to the left of the one or more speaker ports. Further, the parabolic-shaped receptacle has a right receptacle speaker positioned on the frame along the right parabolic curvature to the right of the one or more speaker ports.

Abstract: An electromagnetic transducer includes a diaphragm movable relative to a central axis, a magnetic assembly axially spaced from the diaphragm, and a magnetic gap annularly disposed about the central axis. A voice coil is coupled to the diaphragm and includes spaced first and second coil portions which are at least partially disposed in the magnetic gap. A housing includes a rear frame surrounding and supporting the magnetic assembly, the rear frame having an annular well portion in fluid communication with the magnetic gap. At least one channel is formed in the rear frame in fluid communication with the well portion and extends outwardly beyond the well portion in a radial direction. A vent is provided on an outer surface of the rear frame in fluid communication with the at least one channel, wherein air exits the transducer via the vent to transfer heat from the transducer to the ambient environment.

Abstract: A sound generating device for a vehicle exhaust system has a housing, a sound generator located in the housing, a housing wall that comprises an opening for the sound generator, and a sound channel that extends in the housing. The sound generator is mounted to a shoulder section of the opening such that the opening is closed by the sound generator and a front side and a rear side of the sound generator are assigned to different sides of the opening. The sound channel acoustically connects the rear side of the sound generator with the front side of the sound generator. The opening and the sound generator comprise a central axis and the sound channel runs at least partially around the central axis.

Abstract: The present invention relates to an acoustic signal supply circuit of at least one loudspeaker (HP), this circuit comprising a filtering device of the resonance peak occurring at a given frequency of the supply current, characterized in that the filtering device of the peak is incorporated in a first branch bypassing the intermediate circuit between at least two converters (A, A0), this filtering device being purely electrical in the form of an impedance (Z3) connected, on the one hand, at a point on the intermediate circuit and, on the other hand, to a ground instrumentation, the impedance being called RLC (Z3) for comprising at least one first resistor (R3), at least one first capacitor (C3) and at least one first inductor (L3) arranged in series, the parameters of the first resistor (R3), the first capacitor (C3) and the first inductor (L3) being predetermined as a function of the resonance peak to be filtered.

Abstract: The invention relates in general to the field of high fidelity audio reproduction and to the design process and selection of a sealed loudspeaker for the home and audiophile markets. The sealed loudspeaker has at least one professional sound reinforcement driver, a crossover network, a sealed enclosure, and the enclosure volume is less than 300 liters. The at least one professional sound reinforcement driver has a small compliance volume (Vas) or a large system compliance ratio (?) for a total system quality of between 0.5 and 1.0.

Abstract: A display device having a speaker module includes a display, an ultrasonic speaker and an adjustment module. The speaker module includes at least one first speaker module and at least one second speaker module. The first speaker module is disposed at the display and adapted to emit a first ultrasonic wave. The second speaker module is disposed at the display and adapted to emit a second ultrasonic wave. The first ultrasonic wave and the second ultrasonic wave are intersected to form an audible region. The adjustment module is adapted to control the first speaker module and the second speaker module to rotate relative to the display, so as to drive the audible region to target a user.

Abstract: The systems and methods described herein relate to, among other things, a transducer capable of producing acoustic and tactile stimulation. The transducer includes a rigid mass element disposed on the diaphragm of a speaker. The mass element may optionally be removable and may have a mass selected such that the resonant frequency of the transducer falls within the range of frequencies present in an input electrical audio signal. The systems and methods advantageously benefits from both the fidelity and audio performance of a full-range speaker while simultaneously producing high-fidelity, adjustable and palpable haptic vibrations.

Abstract: An amplifier and an electronic device using the same are provided. The amplifier includes a first acoustic box, a speaker, a second acoustic box, a connection tube and at least one sound guide tube. The first acoustic box has a first sound hole. The speaker faces the first acoustic box. The second acoustic box has at least one second sound hole. The connection tube connects the first acoustic box and the second acoustic box. The sound guide tube is connected to the second sound hole.

Abstract: This invention provides a kind of acoustic structure that uses passive diaphragm unit, it includes speaker unit, passive diaphragm unit, radiant tube; said passive diaphragm unit is located at the back of the cone of said speaker unit; the speaker unit has radiant tube on the sides; the said radiant tube end which is exposed in the air is located at the periphery of the cone of said speaker unit. It has the same orientation as the speaker unit; the said passive diaphragm unit vibrates when it is driven by the said speaker unit, the sound waves produced by the vibration of the said passive diaphragm unit are emitted by the radiant tube and radiant opening, and share the similar vocal point of the said speaker unit. With this, the sound effect of the full range sound is almost identical to the sound point sources, it also reduces the phase difference between the sound effects produced by the cone of speaker unit and the passive diaphragm unit, further enhanced the sound positioning feature.

Abstract: Exemplary embodiments relate to a new audio speaker housing design that includes one or more of several improved features. The housing may include a sealed enclosure designed to have a volume of air that relates to the moving mass of the audio driver piston. The housing may include partition walls that create sub-chamber(s). The partition walls may include concentrically arranged ports into the sub-chambers designed to reduce the sound waves propagating back to the audio driver. The housing may also include inverted dome(s), walls with partial depth ports, and/or walls with an elastomeric lining.

Abstract: Systems and methods for acoustic echo cancellation are provided. An example method includes receiving a reference signal. The reference signal represents at least one sound captured inside an enclosure of a loudspeaker. The loudspeaker is operable to play back a far end signal. The method also includes receiving an acoustic signal. The acoustic signal represents at least one sound captured outside the enclosure of the loudspeaker. The acoustic signal includes at least a near end signal and the far end signal. The method enables attenuation, using the reference signal, the far end signal in the acoustic signal. The reference signal can be captured by a low sensitivity microphone placed inside the enclosure of the loudspeaker. The attenuation of the far end signal may include subtractive cancellation.

Abstract: An acoustic insert for lining a loudspeaker reflex port, the insert comprising an elongate hollow tube formed of a flexible material, having an outer wall sized and configured to seat within the port and an inner wall extending in the elongate direction, the inner wall having a circumference which varies along the length of the insert, When inserted in a port, the insert alters the port resonance so as to vary the acoustic perfoi mance of the loudspeaker.

Abstract: The speaker cabinet (1) includes at least one loudspeaker (2) and at least one port (3), the port having an outlet (32) formed in a wall of the cabinet (1), an inlet (31) inside the cabinet (1), and a casing connecting the inlet (32) and the outlet (31) together, the inlet (32) of the port (3) further having at least one recess in the casing.

Abstract: An electro-acoustic transducer includes a cone, a voice coil connected to the cone, and magnetic circuit that defines a gap within which the voice coil is disposed. The magnetic circuit is configured for creating magnetic flux across the gap for the voice coil to interact with, thereby to drive motion of the cone. A conductor is included for providing an input signal to the voice coil. A first portion of the conductor is fixedly secured to the magnetic circuit such that the first portion of the conductor does not move relative to the magnetic circuit while the cone is in motion.

Abstract: A receiver apparatus includes a first receiver portion and an acoustic filter network. The first receiver portion has a housing and is configured to convert at least one electrical signal into first sound energy having a first frequency range. The acoustic filter network communicates with the first receiver portion and is configured to receive the first sound energy. The acoustic filter network includes at least one sound channel and at least one chamber that communicates with the at least one sound channel. The least one sound channel includes a main branch and a first side branch and the at least one chamber comprises a first chamber. The first side branch communicates with the main branch and the first chamber, and the main branch is configured to receive the first sound energy.