Equalization system to improve the quality of bass sounds within a listening area

Patent metadata

Field	Value
Publication number	US-9008331-B2
Application number	US-2677304-A
Country	US
Kind code	B2
Filing date	Dec 30, 2004
Priority date	Dec 30, 2004
Publication date	Apr 14, 2015
Grant date	Apr 14, 2015

Abstract

Frequency equalization system substantially equalizes the room frequency responses generated by at least one loudspeaker within a listening area so that the frequency responses in the listening area are substantially constant and flat within a desired frequency range. The frequency equalization system uses multiple microphones to measure the impulse responses of the room and uses the impulse responses to design filters to process the audio signals of one or more subwoofers to achieve an improved bass response that is flat across the relevant frequency range. The system employs an algorithm that is a closed-form, non-iterative, mathematical solution and features very short computation time.

First claim

What is claimed is:

1. A method for designing one or more filters to substantially equalize frequency responses within a frequency range in a listening area, comprising:
measuring frequency responses generated by each of a plurality of acoustic transducers in response to an input signal, where the listening area is not an echo free environment;
determining an inverse for each of the frequency responses;
smoothing the inverse for each of the frequency responses to generate corr…

Assignees

• Aggarwal Ashish
• Horbach Ulrich
• Welti Todd
• Harman Int Ind

Inventors

• Aggarwal Ashish
• Horbach Ulrich
• Welti Todd

Classifications

• H04R3/04

  Electricity · mapped topic

• H04R3/12

  Electricity · mapped topic

• H04S7/301 Primary

  Electricity · mapped topic