To reduce engine noise in the cabin of an aircraft a plurality of error microphones is deployed at predetermined locations within the cabin to produce error microphone response signals associated with the engine noise in the cabin. Engine vibration inputs are obtained from sensors coupled to the aircraft engines. A processor is used to code the error microphone response signals into an encoded modal response in the cabin through a coding matrix. A processor is used to apply an adaptive filter to determine a plurality of modal signals needed to cancel the encoded modal response in the cabin. A processor is used to decode the modal signals into speaker input signals through a decoding matrix. Speaker input signals are then sent to a plurality of speakers to reduce the engine noise in the cabin.

A technology is provided that reduces noise heard when a user sits in a seat of an aircraft, without using earphones or headphones. A sound system includes: a control system that generates a control signal for canceling noise in a place close to a head of a user using a seat of an aircraft, from a signal of the noise (noise signal); and a noise-cancellation speaker system including speaker units that emit sound based on the control signal (first noise-cancellation speaker unit, . . . , M-th noise-cancellation speaker unit), the noise-cancellation speaker system being installed at the place close to the head of the user using the seat, wherein assuming that a direction in which the m-th noise-cancellation speaker unit faces the user is an m-th noise-cancellation user direction, the m-th noise-cancellation speaker unit is disposed such that sound emitted from the m-th noise-cancellation speaker unit in the m-th noise-cancellation user direction is canceled in a place other than the place close to the head of the user using the seat, due to bending around of sound emitted from the m-th noise-cancellation speaker unit in an opposite direction to the m-th noise-cancellation user direction.

An active noise cancellation system (1) for cancelling environment noise perceived by a driver or passenger seated in a seat (3) mounted in a cabin of a vehicle, in combination with said seat, the seat comprising a seat cushion (19), a seat back (21) coupled to the seat cushion at a bottom end and extending upwards to a seat shoulder (23), and a headrest (22) coupled to the seat back, extending upwardly from the seat shoulder, the active noise cancellation system comprising an active noise cancellation circuit (ANC) (30), a plurality of microphones (10) mounted in the headrest and connected electrically to the ANC, and a plurality of speakers (16) mounted in the seat and connected electrically to the ANC circuit. The plurality of microphones comprises at least one first microphone mounted on a right side of the headrest and at least one second microphone mounted on a left side of the headrest, and the plurality of speakers comprises at least one first speaker mounted in the seat shoulder on a left side and at least one second speaker mounted in the seat shoulder on a right side, the right speaker configured to generate a noise cancellation sound from a noise signal picked up by the right microphone processed by the ANC circuit and the left speaker configured to generate a noise cancellation sound from a noise signal picked up by the left microphone processed by the ANC circuit.

A sound system, for a user using a seat of an aircraft, an automobile, or the like, that reproduces sound inaudible to users around, without using earphones or headphones, is provided. A sound system for a user using a seat of an aircraft includes: a reproduction apparatus including an n-th reproduction unit (n = 1, ..., N) that outputs a (2n - 1)-th sound signal that is a sound signal obtained based on a subject to be reproduced, and a 2n-th sound signal that is a sound signal with opposite phase to phase of the (2n - 1)-th sound signal, N being an integer equal to or larger than one; and a speaker system including an n-th speaker unit pair (n = 1, ..., N) including a speaker unit that emits sound based on the (2n - 1)-th sound signal (hereinafter, referred to as the positive speaker unit) and a speaker unit that emits sound based on the 2n-th sound signal (hereinafter, referred to as the negative speaker unit), the speaker system being installed at a place close to a head of the user using the seat.

Aircraft, aircraft exterior speaker systems, and methods of projecting sound waves from an exterior of an aircraft are provided. An aircraft includes an outer skin membrane, a vibration actuator, and a controller. The outer skin membrane has an exterior surface that defines an exterior boundary of the aircraft. The vibration actuator is coupled for common vibration with the outer skin membrane. The controller is operatively coupled with the vibration actuator and is configured to generate a command for the vibration actuator based on audible content to be projected from the exterior surface. The controller is further configured to transmit the command to the vibration actuator. The vibration actuator is configured to vibrate in response to receiving the command.

A noise cancellation system for cancelling sounds within a vehicle. The noise cancellation system includes microphones, a camera, a controller, and speakers. The microphones are disposed adjacent to occupant locations, and configured to generate microphone signals representative of noise sounds and cancellation audio sounds. The camera is configured to generate a video signal that captures head configurations of the occupants. The controller is configured to receive rotor control signals, calculate hearing locations based on tracking data of the head configurations of the occupants, and generate a speaker signals based on the hearing locations, the microphone signals, and the rotor control signals. The speakers are configured to generate the cancellation audio sounds. The cancellation audio sounds attenuate the noise sounds.

Various aspects include wearable audio devices wearable audio devices with a control platform for managing external device interaction. In some particular aspects, a wearable audio device includes: an accessory port; at least one processor; and memory including multiple sets of active noise reduction (ANR) configurations (or more generally, multiple profiles), the memory including instructions executable by the at least one processor, where the instructions are configured to: select a first ANR configuration (or more generally, a first profile) upon powering on the wearable audio device, the selection of the first ANR configuration (or first profile) based on an accessory connected to the accessory port, and automatically switch to a second ANR configuration (or more generally, a second profile) in response to a trigger, where the second ANR configuration (or second profile) is different from the first ANR configuration (or first profile).

An urban air mobility (UAM) noise reduction system and method are provided, where the UAM noise reduction system includes a UAM configured to detect and to provide rotation per minute (RPM) information of a propeller and location coordinate information, and a noise canceling device configured to predict a noise canceling sound wave amplitude on the basis of the RPM information of the propeller and the location coordinate information received through the UAM and to output a noise canceling sound wave corresponding to the predicted noise canceling sound wave amplitude to the UAM.

Provided are methods and apparatus for enhancing a signal-to-noise ratio. In an example, provided is an apparatus configured to modify audio to better match the way the human brain processes audio by modifying the audio to a form which takes advantage of human echolocation capabilities. When humans listen to audio, they subconsciously listen for an echo and thus subconsciously focus on listening to, and for, meaningful information in audio. The focus causes humans to ignore noise in the audio, which results in enhancing a signal-to-noise ratio.

A technique for reducing noise in a listening environment. The technique includes dividing the listening environment into a plurality of zones, where each zone is associated with a different active noise cancellation (ANC) system. A boundary between a first zone included in the plurality of zones and a second zone included in the plurality of zones comprises open space. The technique further includes assigning a plurality of acoustic sensors and a plurality of speakers to the ANC system associated with each zone included in the plurality of zones. The technique further includes, for each zone included in the plurality of zones, acquiring acoustic data via the plurality of acoustic sensors, processing the acoustic data, via a processor, to generate noise cancellation signals, and outputting the noise cancellation signals via the plurality of speakers.