Abstract: An audio system comprises a plurality of membranes within an enclosure. A first surface of each of the plurality of membranes is part of a shared back volume within the enclosure and pressure within the shared back volume is configured to be isobaric. A second surface of each of the membranes is part of a front volume within the enclosure that includes a plurality of ports. A controller of the audio system is configured to drive the plurality of membranes. In a mode of operation, the controller is configured to match audio output between the plurality of ports, forming pressure waves of equal amplitude and opposite phase and generating a substantially dipole or linear quadrupole sound wave radiation pattern for frequencies above a predefined threshold and mismatch audio output between the plurality of ports for frequencies at or below the predefined threshold to generate a substantially monopole or cardioid sound wave radiation pattern.

Abstract: An audio system includes a speaker having a transducer, where the speaker is positioned within an enclosure that forms a front volume and a rear volume on opposite sides of the transducer. The rear part of the enclosure defining the rear volume is formed of an acoustic metamaterial that defines a plurality of channels within the rear volume, where the number and dimensions of the channels is configured to virtual increase the rear volume to amplify a bass portion of sound produced by the speaker. In addition, the channels may be configured to match an impedance of the front volume to serve as an absorber for high frequency audio.

Abstract: Apparatuses, systems, and methods for detecting sound via a wearable device are described herein. An example system may include a pair of glasses that include a nose pad that, when the pair of glasses are worn by a user, contacts a portion of a nose of the user at a contact point and a vibration sensor, included in the nose pad. The vibration sensor may be configured to receive vibrations produced by the user via the contact point, and convert the received vibrations into an electrical signal representative of the received vibrations. The system may also include a control device configured to receive the electrical signal, and convert the electrical signal into digital audio data. Various other apparatuses, systems, and methods are described herein.

Abstract: An electronic device may include one or more terminals configured to provide a voltage signal to an actuator. The electronic device may detect a current associated with the voltage signal provided by the terminal to the actuator. The electronic device may determine an impedance across associated with the actuator based on the voltage signal and the electrical current. The electronic device may compare the impedance to a threshold impedance to determine whether there is sufficient skin contact with the actuator. The electronic device may provide audio via cartilage conduction if there is sufficient contact based on comparing the impedance to the threshold impedance, or may output a notification to the user to adjust placement of the electronic device to improve contact.

Abstract: Embodiments relate to an audio system that performs equalization of audio signals based on one or more diffuse field head-related transfer functions (HRTFs) and device-specific data. User-specific data and device-specific data (i.e., transducer-specific data) are applied to an acoustic model to predict an acoustic response for a user. An equalization filter is then determined using the acoustic response and the one or more diffuse field HRTFs. The equalization filter is applied to a processed version of an audio signal to create a modified version of the audio signal. The modified version of the audio signal is presented to the user via a transducer array of the audio system. The audio system can further include a microphone assembly that reduces the Helmholtz resonance effect.

Abstract: Embodiments relate to an audio system that performs equalization of audio signals based on one or more diffuse field head-related transfer functions (HRTFs) and device-specific data. User-specific data and device-specific data (i.e., transducer-specific data) are applied to an acoustic model to predict an acoustic response for a user. An equalization filter is then determined using the acoustic response and the one or more diffuse field HRTFs. The equalization filter is applied to a processed version of an audio signal to create a modified version of the audio signal. The modified version of the audio signal is presented to the user via a transducer array of the audio system. The audio system can further include a microphone assembly that reduces the Helmholtz resonance effect.

Abstract: An audio system comprises an array of transparent piezoelectric transducers on a transparent surface. Each transparent piezoelectric transducer includes one or more piezoelectric layers and one or more conductive layers that are substantially transparent to visible light. A transparent piezoelectric transducer may include, e.g., a first conductive layer, a first piezoelectric layer on the first conductive layer, and a second conductive layer on the first piezoelectric layer. Or in another example, the transparent piezoelectric transducer includes many (e.g., 20-30) piezoelectric layers and many (e.g., 20-30) conductive layers.

Abstract: An in-ear device is implemented as part of an audio system to present a user with improved audio content within an artificial reality system. The in-ear device is a fully integrated device with an internal microphone, an external microphone, and a transducer in which portions of the transducer form portions of the body of the device. This integration of transducer into the body of the in-ear device reduces the size of the in-ear device and allows for placement deeper within the ear canal of the user. The transducer generates audio content based on instructions received from an audio system that may be located on a device that is external to the in-ear device. The external microphone provides hear-through functionality, while the internal microphone provides feedback information to the audio system.

Abstract: A sensor system includes an actuator, an accelerometer coupled with the actuator, a rigid member, a transducer, and one or more processors. The actuator generates motion. The accelerometer outputs an acceleration signal responsive to at least the motion of the actuator. The rigid member extends from a first end coupled with the accelerometer to a second end. The transducer is coupled with the second end of the rigid member. The transducer can be configured to couple with a load, and can output a force signal responsive to at least a portion of the motion of the actuator transmitted to the transducer via the rigid member. The one or more processors determine a mechanical impedance of the load based at least on the acceleration signal and the force signal.

Abstract: A coil assembly for integration into a transducer is presented. The coil assembly may include a metal bobbin assembly, a wire coil, and one or more nonconductive printed circuit board (PCB) stiffeners. A speaker that renders micro noise in an artificial reality environment for improving simulated presence is further presented. The speaker may generate a plurality of micro noises based in part on the determined state of the virtual object. The speaker may spatialize the plurality of micro noises, such that the plurality of micro noises appears to originate from the virtual object. A speaker for speaker diaphragm motion detection using optical MEMS sensors is further presented. Optical MEMS sensors are used to optically monitor displacement of one or more portions of a speaker diaphragm. The speaker may be configured to determine that a speaker diaphragm is in rocking mode and move the speaker diaphragm out of rocking mode.

Abstract: A microelectromechanical system (MEMS) coil assembly is presented herein. In some embodiments, the MEMS coil assembly includes a foldable substrate and a plurality of coil segments. Each coil segment includes a portion of the substrate, two conductors arranged on the portion of the substrate. The substrate can be folded to stack the coil segments on top of each other and to electrically connect first and second conductors of adjacent coil segments. In some other embodiments, the MEMS coil assembly includes a plurality of coil layers stacked onto each other. Each coil layer includes a substrate and a conductor to form a coil. The conductors of adjacent coil layers are connected through a via. The MEMS coil assembly can be arranged between a pair of magnets. An input signal can be applied to the MEMS coil assembly to cause the MEMS coil assembly to move orthogonally relative to the magnets.

Abstract: Embodiments relate to an audio system configured to provide enhancement of low audio frequencies. The audio system includes a tissue transducer and a speaker coupled to the tissue transducer. The tissue transducer is configured to be coupled to a tissue of a user (e.g., pinna of a user's ear). The speaker includes a diaphragm having a first surface and a second surface that is opposite the first surface. The first surface is configured to generate a first set of airborne acoustic pressure waves, and the second surface is configured to generate a backpressure. The tissue transducer is driven by the backpressure to vibrate the tissue to form a second set of acoustic pressure waves. The first set of airborne acoustic pressure waves and the second set of acoustic pressure waves together form audio content that is presented to the user.

Abstract: An electronic device may include one or more terminals configured to provide a voltage signal to an actuator. The electronic device may detect a current associated with the voltage signal provided by the terminal to the actuator. The electronic device may determine an impedance across associated with the actuator based on the voltage signal and the electrical current. The electronic device may compare the impedance to a threshold impedance to determine whether there is sufficient skin contact with the actuator. The electronic device may provide audio via cartilage conduction if there is sufficient contact based on comparing the impedance to the threshold impedance, or may output a notification to the user to adjust placement of the electronic device to improve contact.

Abstract: Embodiments relate to an audio system configured to provide enhancement of low audio frequencies. The audio system includes a tissue transducer and a speaker coupled to the tissue transducer. The tissue transducer is configured to be coupled to a tissue of a user (e.g., pinna of a user's ear). The speaker includes a diaphragm having a first surface and a second surface that is opposite the first surface. The first surface is configured to generate a first set of airborne acoustic pressure waves, and the second surface is configured to generate a backpressure. The tissue transducer is driven by the backpressure to vibrate the tissue to form a second set of acoustic pressure waves. The first set of airborne acoustic pressure waves and the second set of acoustic pressure waves together form audio content that is presented to the user.

Abstract: An electronic device may include one or more terminals configured to provide a voltage signal to an actuator. The electronic device may detect a current associated with the voltage signal provided by the terminal to the actuator. The electronic device may determine an impedance across associated with the actuator based on the voltage signal and the electrical current. The electronic device may compare the impedance to a threshold impedance to determine whether there is sufficient skin contact with the actuator. The electronic device may provide audio via cartilage conduction if there is sufficient contact based on comparing the impedance to the threshold impedance, or may output a notification to the user to adjust placement of the electronic device to improve contact.

Abstract: An in-ear device is implemented as part of an audio system to present a user with improved audio content within an artificial reality system. The in-ear device is a fully integrated device with an internal microphone, an external microphone, and a transducer in which portions of the transducer form portions of the body of the device. This integration of transducer into the body of the in-ear device reduces the size of the in-ear device and allows for placement deeper within the ear canal of the user. The transducer generates audio content based on instructions received from an audio system that may be located on a device that is external to the in-ear device. The external microphone provides hear-through functionality, while the internal microphone provides feedback information to the audio system.

Abstract: An audio system comprises an array of transparent piezoelectric transducers on a transparent surface. Each transparent piezoelectric transducer includes one or more piezoelectric layers and one or more conductive layers that are substantially transparent to visible light. A transparent piezoelectric transducer may include, e.g., a first conductive layer, a first piezoelectric layer on the first conductive layer, and a second conductive layer on the first piezoelectric layer. Or in another example, the transparent piezoelectric transducer includes many (e.g., 20-30) piezoelectric layers and many (e.g., 20-30) conductive layers.

Abstract: A dipole speaker assembly comprises a transducer section, a front volume section, and a rear volume section. The transducer section includes a frame and piezoelectric actuators coupled to the frame. The piezoelectric actuators are configured to generate an acoustic pressure wave. The transducer section includes a first side and a second side, the second side being opposite the first side. The front volume section is coupled to the first side to form a front cavity, the front volume section including an aperture from which the generated acoustic pressure wave exits the front volume section towards an ear canal of a user. The rear volume section is coupled to the second side to form a rear cavity. The generated acoustic pressure wave exiting the rear volume section cancels the generated acoustic pressure wave exiting the front volume section in the far field.

Abstract: An in-ear device is implemented as part of an audio system to present a user with improved audio content within an artificial reality system. The in-ear device is a fully integrated device with an internal microphone, an external microphone, and a transducer in which portions of the transducer form portions of the body of the device. This integration of transducer into the body of the in-ear device reduces the size of the in-ear device and allows for placement deeper within the ear canal of the user. The transducer generates audio content based on instructions received from an audio system that may be located on a device that is external to the in-ear device. The external microphone provides hear-through functionality, while the internal microphone provides feedback information to the audio system.

Abstract: An audio system comprises an array of transparent piezoelectric transducers on a transparent surface. Each transparent piezoelectric transducer includes one or more piezoelectric layers and one or more conductive layers that are substantially transparent to visible light. A transparent piezoelectric transducer may include, e.g., a first conductive layer, a first piezoelectric layer on the first conductive layer, and a second conductive layer on the first piezoelectric layer. Or in another example, the transparent piezoelectric transducer includes many (e.g., 20-30) piezoelectric layers and many (e.g., 20-30) conductive layers.