A microphone system, comprises a first transducer, for generating a first acoustic signal, and a second transducer, for generating a second acoustic signal. A high-pass filter receives the first signal and generates a first filtered signal, and a low-pass filter receives the second signal and generates a second filtered signal. An adder forms an output signal of the microphone system as a sum of the first filtered signal and the second filtered signal.

The Application relates to optically transparent electrostatic transducers. In some embodiments, the transducers comprise graphene. Such transducers are capable of functioning as acoustic sensors and/or transmitters as a singulated device or in an array configuration. Also provided are methods of manufacturing and using such transducers.

The disclosure relates in general to on-ear transition detection, and in particular to on-ear transition detection circuitry comprising: a monitoring unit operable to monitor a speaker current flowing through a speaker and/or a speaker voltage induced across the speaker, and to generate a monitor signal indicative of the speaker current and/or the speaker voltage; and an event detector operable to detect a qualifying disturbance in a sensor signal indicative of a qualifying pressure change incident on the speaker caused by the speaker transitioning from an on-ear state to an off-ear state or vice versa, wherein the sensor signal is, or is derived from, the monitor signal.

In accordance with embodiments of the present disclosure, a device may include a piezoelectric speaker for generating sound, a microphone, and a controller communicatively coupled to the speaker and the microphone. The controller may be configured to receive a first signal from the piezoelectric speaker, the first signal induced at least in part by sound incident on the speaker other than sound generated by the piezoelectric speaker, receive a second signal from the microphone, the second signal induced by sound incident on the microphone, process at least one of the first signal and the second signal to determine at least one characteristic of sound incident upon at least one of the piezoelectric speaker and the microphone, and select at least one of the microphone and the piezoelectric speaker as a signal source for incident sound based on the at least one characteristic.

Example embodiments may include one or more of receiving an electrical sound emission signal from a sound controller, interrupting reception of the electrical sound emission signal, by a sound emission interruption circuit connected to a sound emitter, and receiving an electrical ambient sound signal via a sound detection circuit, based on ambient sound sensed by the sound emitter when the reception of the electrical sound emission signal is interrupted by the sound emission interruption circuit.

Monitoring circuitry, comprising: a current monitoring unit operable to monitor a speaker current flowing through a speaker and generate a monitor signal indicative of that current; and a controller operable, based on a control signal, to control the current monitoring unit to control whether the monitor signal is generated and/or a property of the monitor signal.

The present disclosure is directed to a device that includes a headphone speaker housing that includes a coil having a first terminal and a second terminal that is configured to operate in a sound generation mode and a battery charging mode. A class D amplifier circuit is configured to rectify in a battery charging mode and amplify in a sound generation mode, the class D amplifier is coupled to the first terminal and the second terminal of the coil. The class D amplifier including a first, second, third, and fourth switch, the first terminal coupled between the first and second switch, the second terminal coupled between the third and fourth switch. An audio generation circuit having a third terminal and a fourth terminal, the third terminal coupled between the first and third switch of the class D amplifier and the fourth terminal coupled between the second and fourth switch of the class D amplifier. A battery charging circuit coupled to the third terminal and the fourth terminal.

A display device includes a display panel including a display layer including light-emitting elements disposed on a substrate, and a sensor electrode layer disposed on the display layer. The sensor electrode layer includes a first sound electrode and a second sound electrode; a vibration layer electrically contacting the first sound electrode and the second sound electrode and being deformed in response to a first sound driving voltage applied to the first sound electrode and a second sound driving voltage applied to the second sound electrode; and sensor electrodes disposed on the vibration layer. The sensor electrodes sense an input.

Audio circuitry, comprising: a speaker driver operable to drive a speaker based on a speaker signal; a current monitoring unit operable to monitor a speaker current flowing through the speaker and generate a monitor signal indicative of that current; and a microphone signal generator operable, when external sound is incident on the speaker, to generate a microphone signal representative of the external sound based on the monitor signal and the speaker signal.

A speaker system with acoustic event detection, the speaker system including a number of speakers, a head unit including an output circuit structured to output an output signal to the speakers to cause the speakers to output an audible sound, and an acoustic event detection module structured to receive signals from the speakers and to detect an acoustic event based on the signals received from the speakers.