A voice-controlled electronic device that includes an axisymmetric device housing having a longitudinal axis bisecting opposing top and bottom surfaces and a side surface extending between the top and bottom surfaces. The device can further include a plurality of microphones disposed within the device housing and distributed radially around the longitudinal axis; a processor configured to execute computer instructions stored in a computer-readable memory for interacting with a user and processing voice commands received by the plurality of microphones and first and second transducers configured to generate sound waves within different frequency ranges.

A loudspeaker device comprises first and second diaphragms (12, 14) arranged co-axially in an opposed relation to each other to cancel mechanical vibrations. Each diaphragm has multiple voice coils, with the voice coils of the first and second diaphragms (12, 14) arranged in the same plane to reduce the height of the loudspeaker device.

A movable diaphragm comprises a layer having a disc shape with undulating waves that extend from an inner diameter to an outer diameter. The layer is to be offset from a stationary surface and displaced toward the stationary surface, the displacement of the layer to effectively cause a respective compression and rarefaction of air between the layer and the stationary surface to an external environment. An annular surround is to seal outer edge portion of the layer to a transducer component, the surround having compliant properties to allow the displacement of the layer relative to the stationary surface and the transducer component without breaking the seal. The undulations increases an effective surface area of the layer to lower an overall size of the transducer that would otherwise be needed for a low frequency speaker.

Systems and methods are herein described for a coaxial loudspeaker. The loudspeaker may comprise a compression driver having a first diaphragm assembly including a first magnet, and a first diaphragm coupled to a first voice coil, and a second diaphragm assembly including a second magnet and a second diaphragm coupled to a second voice coil. The compression driver may further comprise a third diaphragm assembly including a third diaphragm coupled to a third voice coil.

A compression driver is provided. In one embodiment, the compression driver comprises an annular diaphragm, a phasing plug, and a housing, wherein the housing has a rectangular exit proximate to a blade of the phasing plug.

A loudspeaker comprising: an acoustic diaphragm having front and rear surfaces, the acoustic diaphragm in use being driven so as to vibrate and radiate acoustic waves from its front surface in a forward direction away from the loudspeaker and from its rear surface in a rearward direction, and a drive unit located rearwardly or to the front/outside of the diaphragm, there being at least one open duct leading in a rearward direction away from the diaphragm, in which the at least one open duct has a cross-sectional area which decreases in the rearward direction, and in which acoustic waves radiated from the rear surface of the diaphragm pass through the open duct before contacting a front surface of an acoustic metamaterial absorber located generally behind the drive unit and immediately to the rear of the duct.

A compression driver including an acoustic outlet duct, a magnetic assembly having a permanent magnet and an air gap, a vibrating membrane with a movable coil adapted and configured to move inside the air gap, where the vibrating membrane includes a first face facing a first chamber communicating with the outlet duct, where the first chamber is a compression chamber, a second face opposite to the first face and facing a second chamber communicating with the air gap and opposite to the first chamber, where the compression driver includes at least one acoustic connection duct which puts in communication the second chamber with the acoustic outlet duct.

In at least one embodiment, an audio system for extracting online parameters is provided. The system includes a loudspeaker and at least controller. The loudspeaker transmits an audio signal in a listening environment. The at least one controller includes a signal processing block and an adaptive filter. The signal processing block is programmed to provide a driving signal u(n) to drive the loudspeaker to transmit the audio signal. The adaptive filter is programmed to receive the driving signal and to receive a first varying signal i(n) from the loudspeaker in response to the loudspeaker transmitting audio signal. The adaptive filter is further programmed to generate an admittance curve for the loudspeaker based at least on the driving signal and the first varying signal.

An air pulse generating element is disclosed. The air pulse generating element includes a membrane, actuated according to a driving signal; a plate, wherein a chamber is formed between the plate and the membrane; wherein during a first phase of the driving signal, the membrane is actuated to change a volume within the chamber to generate an air pulse; wherein during a second phase of the driving signal, the membrane is actuated such that a gap is temporarily formed; wherein the temporarily formed gap is configured to provide a temporary air shunt to accelerate an air balancing process between a first air pressure at a first side of the membrane and a second air pressure at a second side of the membrane.

A sound producing device is disclosed. The sound producing device includes a first air pulse generating element, driven by a first driving signal comprising a first electrical pulse, the first electrical pulse comprises a first transition edge with a first transition polarity; and a second air pulse generating element, disposed adjacent to the first air pulse generating element, driven by a second driving signal comprising a second electrical pulse, the second electrical pulse comprises a second transition edge with a second transition polarity; wherein the first transition polarity is opposite to the second transition polarity; wherein the first transition edge generally coincides with the second transition edge; wherein air pulses generated by the first or the second air pulse generating element produce non-zero offset in terms of sound pressure level.