A2 Acoustics Ab

Scania Cv Ab

Magna International Inc.

Urban Emborg

Todd Deaville

Thomas Pilette

Mats Olle Gustavsson

Fredrik Samuelsson

Siv Leth

Gustav Kristiansson

Sohan Sarin

Johan Hammar

The invention refers to a device for sound control in a space () with a sound field from at least one sound source (). The device includes a pulse sensor (), which provides a pulse signal from the sound source (). Moreover, the device includes a number of sound influencing members () for reducing the sound field in the space () and a number of sound sensors (), which sense the actual sound field in the space and provide an error signal. A control unit includes a signal supplied device (), which receives a pulse signal and supplies a first signal to an adaptive filter (). The filter has a number of filter coefficients and generates a drive signal for each sound influencing member (). The signals supply device also supplies second signals to a calculating member (), which calculates the value of the filter coefficients by the second signals and the error signals for updating the adaptive filter (). A detecting member detects phase and frequency of the pulse signal and a coefficient table provides two sets of coefficients for generating the second signals from detected phase and frequency of the pulse signal.

Device for active sound control in a space

A device at an acoustic liner for an apparatus generating sound comprises means ( ) adapted to enable changes of the value of the acoustic impedance of the liner.

Device at an acoustic liner

Growing community of inventors

Ljungsbro, Sweden

Urban Emborg