A computing device, such as a headset, provides for selective sound level reduction or sound level amplification for sounds made in a local area. The computing device includes a speaker assembly and a controller. The controller receives an audio signal from a second computing device, such as a second headset, via a wireless connection with the computing device. The audio signal describes a sound made by a user of the second computing device. The audio signal arrives at the computing device prior to the sound. The controller determines an audio filter to selectively adjust an amplitude of the sound and applies the audio filter to the audio signal to generate audio content. The controller presents, via the speaker assembly, the audio content to a user such that the presented audio content combines with the sound to selectively adjust the amplitude of the sound.

Acoustic imaging systems having sound forming lenses and sound amplitude detectors and associated methods are disclosed herein. According to an aspect, an acoustic imaging system includes a sound forming lens configured to focus sound waves received from a plurality of directions onto respective predetermined areas. The acoustic imaging system also includes sound amplitude detectors positioned to receive the focused sound waves at the predetermined areas and to output signals indicative of the directions of receipt of the sound waves by the sound forming lens.

A recording play method, terminal and non-transitory computer-readable storage medium are provided, where the recording play method includes obtaining a recording file, wherein the recording file comprises saved recording data in all sound source directions via the at least three microphones; receiving a first gesture on an interface displayed on the screen, wherein the first gesture indicates a first recording play direction; determining, according to the first gesture, a first recording data matching the first recording play direction from the saved recording data in all sound source directions; and playing the first recording data matching the first recording play direction.

An acoustically-transmissive structure with a three-dimensional distribution of subwavelength acoustic refractive indices to diffractively concentrate acoustic waves incident on an effective aperture of the structure from a range of incidence directions between a minimum acceptance angle and a maximum acceptance angle to a smaller effective aperture. In a specific embodiment, an acoustic system may include a plurality of electroacoustic transducers and an acoustic structure having a first, larger effective aperture with a three-dimensional distribution of acoustic refractive indices. The acoustic structure diffractively concentrates acoustic waves received at a first set of angles of incidence to a first electroacoustic transducer and diffractively concentrates acoustic waves received at a second set of angles of incidence to a second electroacoustic transducer. The effective apertures of each of the first and second electroacoustic transducers has a smaller effective aperture relative to the larger effective aperture of the acoustic structure.

Arrangements for communication and/or noise attenuation within an aircraft, and aircraft and methods for making aircraft including such arrangements are provided. In one example, an arrangement includes an array of first microphones cooperatively configured to be directed towards a first aircraft operator when disposed in a first cockpit seat to receive a first communication input from the first aircraft operator. An array of first speakers is cooperatively configured to be directed towards the first aircraft operator when disposed in the first cockpit seat to provide a first communication output to the first aircraft operator.

A recording play method, terminal and non-transitory computer-readable storage medium are provided, where the recording play method includes obtaining a recording file, wherein the recording file comprises saved recording data in all sound source directions via the at least three microphones; receiving a first gesture on an interface displayed on the screen, wherein the first gesture indicates a first recording play direction; determining, according to the first gesture, a first recording data matching the first recording play direction from the saved recording data in all sound source directions; and playing the first recording data matching the first recording play direction.

A recording method, a recording play method, apparatuses and terminals, where the recording method comprises obtaining, by a terminal, recording data in all sound source directions input by at least three microphones, and generating, by the terminal, a recording file according to the obtained recording data, wherein the recording file saves the recording data in all the sound source directions.

Various implementations described herein are directed to a trolling device having a motor with a propeller coupled to the motor and a shaft configured to couple or mount the motor to a watercraft. The trolling device may include a housing encapsulating the motor and the housing may include a nosecone. A sonar transducer assembly may be incorporated within the housing or nosecone including a phased array configured to transmit sonar beams into an underwater environment.

A numerically stable and computationally efficient method for updating and downdating during MVDR (minimum variance distortionless response) adaptive beamforming. The method involves downdating and updating of the triangular (Cholesky) factor of the covariance matrix. The covariance matrix is never explicitly formed, but rather is partitioned and expanded after substituting in the Cholesky factors.

Disclosed is a system, method, and aircraft for controlling acoustic radiation from an aircraft comprising a plurality of rotor systems and a noise controller configured to regulate acoustic radiation from the plurality of rotor systems. The noise controller can be configured to regulate a commanded flight setting from the flight control system and to output a regulated flight setting to the plurality of rotor systems. Based on the regulated flight setting, the plurality of rotor systems are configured to generate, individually and in aggregate, acoustic radiation having a target acoustic behavior. In certain aspects, the noise controller can change the directionality of acoustic radiation from the plurality of rotor systems, or otherwise tune the acoustic radiation to reduce detectability or annoyance.