A method for feedforward noise cancellation in an enclosed space within a structure is provided. The method comprises placing a microphone array inside an inner surface of the enclosed space and conducting modal testing on an outside surface of the enclosed space, wherein the modal testing comprises multiple incoherent noise sources corresponding to locations of microphones in the microphone array. Noise generated by the modal testing is processed to create a number of acoustic mathematical models of the enclosed space. In response to incoherent noise within the enclosed space, a noise canceling signal is generated according to an output of the mathematical models.

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 includes a seat including a seatback having a first dipole subwoofer, a second dipole subwoofer, a first speaker, and a second speaker; and a seat bottom having a third speaker. The first dipole subwoofer, the second dipole subwoofer, the first speaker, the second speaker, and/or the third speaker may be configured to receive audio signals from a receiver and provide sound corresponding to the audio signals toward an occupant position of the seat. The third speaker may be directed toward the seat back. The first dipole subwoofer, the second dipole subwoofer, the first speaker, the second speaker, and/or the third speaker may be configured to provide a sound zone for said occupant that facilitates (i) hearing of the sound by said occupant, and/or (ii) limiting transmission of the sound beyond the seat.

Implementations of the subject technology provide user tracking headrest audio control. For example, a seat may have a headrest and one or more speakers mounted to the headrest for providing audio output to an occupant of the seat. Because the head of the occupant may be disposed in the near field of the headrest speakers when the occupant is seated in the seat, movements of the occupant's head and/or ears may affect the acoustic experience of the occupant. Aspects of the subject technology provide for modifications to audio output(s) from one or more speaker(s) mounted in a headrest, based on tracking of the location of the occupant's head and/or ears relative to the location(s) of the speaker(s).

Seats that include sound cancelation systems are described. An example vehicle bench seat has a first backrest, a first speaker, a second backrest, a second speaker, a central portion, and a seat base. The first speaker is disposed within the first backrest and the second speaker is disposed within the second backrest. Each of the first and second speakers emit primary sound waves and secondary sound waves. The secondary sound waves of the first speaker are 180 degrees out of phase with the primary sound waves of the first speaker and the secondary sound waves of the second speaker are 180 degrees out of phase with the primary sound waves of the second speaker. The central portion includes channels that direct the secondary sound waves emitted by the first and second speakers into the vehicle cabin to cancel undesired primary sound waves.

A first cancellation signal output from a first speaker cancels noise at a first cancellation point, which is a typical position of the right ear of a user, together with a second cancellation signal output from a second speaker. In addition, the second cancellation signal output from the second speaker cancels noise at a second cancellation point, which is a typical position of the left ear of the user, together with the first cancellation signal output from the first speaker. The first speaker and the second speaker are arranged side by side on a second line segment, which passes through the midpoint of a first line segment connecting the first cancellation point and the second cancellation point to each other and is perpendicular to the first line segment, and a range where the relationship between noise and the first cancellation signal and the second cancellation signal is the same as that at the cancellation point is extended.

Disclosed herein is a system for facilitating stress adaption in a workstation. Accordingly, the system may include microphones disposed on the workstation. Further, the one or more microphones may be configured for generating first sound signals of first sounds associated with an environment of the workstation. Further, the system may include a processing device communicatively coupled with the microphones. Further, the processing device may be configured for analyzing the first sound signals, determining first sound characteristics of the first sounds, determining second sound characteristics of second sounds, and generating second sound signals for the one or more second sounds. Further, the system may include acoustic devices disposed on the workstation. Further, the acoustic devices may be communicatively coupled with the processing device. Further, the acoustic devices may be configured for emitting the second sounds based on the second sound signals. Further, the second sounds destructively interfere with the first sounds.

A noise reduction device includes a processor that converts a noise signal collected by a microphone disposed in a control space into a noise signal in a frequency domain, a storage that stores the converted noise signal in the frequency domain as a reference signal, and a signal generator that generates a noise reduction signal for reducing the noise signal collected by the microphone at a control position of the control space. The processor determines whether or not the noise signal is non-stationary noise based on a frequency characteristic of the converted noise signal in the frequency domain and a frequency characteristic of the reference signal. When it is determined that the noise signal is the non-stationary noise, the processor controls the signal generator so as to cancel generation of the noise reduction signal.

The present disclosure provides an automobile and a noise reduction method thereof, wherein the automobile includes an automobile body having an accommodating space and a plurality of doorways communicating with the accommodating space, a door configured for closing each doorway, at least one seat, at least one sound collecting device mounted on the automobile body at a periphery of each door, at least two sound devices mounted on at least one seat, and a processor electrically connected to all the sound devices and all the sound collecting devices. A noise reduction system composed of all the sound devices, all the sound devices, and the processor can perform noise reduction on a preset area in the accommodating space. The embodiments of the present invention expand and reuse a system composed of original sound collecting devices and sound devices in the automobile, without stacking materials on the doors or the automobile body.

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.