A first seat noise control device corrects sound collected by a microphone to sound at a listening position of a user seated on a first seat, generates a cancel sound that cancels, at the first seat, the sound of a second seat audio source output from a second seat speaker by using an adaptive filter, and outputs the cancel sound from a first seat speaker. A second seat noise control device corrects the sound collected by the microphone to sound at the listening position of the user seated on the second seat, generates a cancel sound that cancels, at the second seat, the sound of a first seat audio source output from the first seat speaker using an adaptive filter, and outputs the cancel sound from the second seat speaker.

With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

A method and a system for creating a plurality of sound zones within an acoustic cavity is provided. The method comprises: providing a plurality of actuators within the acoustic cavity, each for generating a respective acoustic output in response to a respective drive signal, providing, for each of the plurality of actuators, an adaptive filter for receiving a respective input signal, and generating a respective output signal, providing, for each of the adaptive filters, at least one filter coefficient, providing a plurality of error sensors within the acoustic cavity, each for generating a respective error signal e, representing a respective sound detected by the respective error sensor, providing an audio data signal x(n) for generating a desired sound in a desired sound zone of the plurality of sound zones, determining, for the desired sound zone, a set of actuator generation coefficients kg.sub.k, a set of actuator exclusion coefficients ke.sub.k, wherein k refers to a k.sub.th actuator, k=1, 2, 3 . . . , and a set of sensor weighting coefficients me.sub.m wherein m refers to a m.sub.th error sensor, m=1, 2, 3 . . . .

A device for reducing crosstalk in an audio system that has first and second pairs of loudspeakers and first and second audio sources. The device is connected to each audio source and to at least the first pair of loudspeakers. The device includes a module for acquiring first audio signals from the first source and second audio signals from the second source, a module for determining crosstalk reduction filters resulting from a loudspeaker of the second pair, a module for calculating corrective signals, by applying the reduction filters to the second audio signals, and a module for generating corrected audio signals for the first pair, obtained from the first audio signals and corrective signals. Each reduction filter is obtained from transfer functions, each representing an acoustic path between a loudspeaker and a user's ear.

A first seat noise control device corrects sound collected by a microphone to sound at a listening position of a user seated on a first seat, generates a cancel sound that cancels, at the first seat, the sound of a second seat audio source output from a second seat speaker by using an adaptive filter, and outputs the cancel sound from a first seat speaker. A second seat noise control device corrects the sound collected by the microphone to sound at the listening position of the user seated on the second seat, generates a cancel sound that cancels, at the second seat, the sound of a first seat audio source output from the first seat speaker using an adaptive filter, and outputs the cancel sound from the second seat speaker.

With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

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.

In the noise reduction device, the sound receiver receives a noise signal acquired from the microphone. The sound source input unit receives an input of a sound source signal from a sound source. The sound adjuster changes the intensity of the sound source signal relative to the intensity of the noise signal. The control sound generator generates a control sound signal that reduces the noise signal. The control unit controls the change of the intensity of the sound source signal and the generation of the control sound signal. The sound output outputs the control sound signal to the speaker. The sound output outputs to the speaker the sound source signal at the intensity changed by the sound adjuster.

[Object] To reduce the influence of noise in a more preferred aspect even in an environment in which a user hears an acoustic sound output to an open space.

[Solution] A signal processing device includes: a generation unit configured to generate a first noise reduction signal for driving a first acoustic device which outputs a first acoustic sound for reducing noise; and an acquisition unit configured to acquire a sound collection result of an acoustic sound collected by a predetermined sound collection unit, the acoustic sound including the first acoustic sound propagating from the first acoustic device via a first propagation path and a second acoustic sound propagating from a second acoustic device different from the first acoustic device via a second propagation path. The generation unit generates the first noise reduction signal on a basis of the sound collection result and a cancellation signal based on a second noise reduction signal for driving the second acoustic device.

Estimated output signals of the reference signals are generated using an estimated filter path transfer function that provides an estimated effect on sound waves traversing a physical path, the estimated filter path transfer function performing processing according to a diagonalization matrix and reference signals. Anti-noise signals are generated from the reference signals using an adaptive filter driven by learning unit signals received from a learning algorithm unit, the learning unit signals based in part on error output signals generated from the estimated output signals, the anti-noise signals including signals per sound zone and per reference signal, each sound zone including a microphone and one or more loudspeakers. A sum across references is performed on the anti-noise signals to generate a set of output signals per sound zone. The set of output signals are processed by the diagonalization matrix to generate a set of output signals per loudspeaker.