07333618 is referenced by 31 patents and cites 12 patents.

Systems and methods for ambient noise compensation are disclosed. One example of a system includes a variable amplifier, a source sound processor, an area sound processor, and an adjustment circuit. The variable amplifier adjusts an audio input signal to generate an audio output signal with an appropriate level so that the audio output signal is audible over noise in a listening area. The source sound processor and the area sound processor may split the audio output signal and a monitoring signal into frequency bands, and may compare these signals band-by band to find differences that represent time-varying noise in the monitoring signal. These differences may be modified to account for the acoustic response of the listening area and for constant-level background noise in the listening area. The adjustment circuit controls the variable amplifier in response to these differences.

Title
Ambient noise sound level compensation
Application Number
10/669290
Publication Number
7333618 (B2)
Application Date
September 24, 2003
Publication Date
February 19, 2008
Inventor
Brian R Ellison
Salt Lake City
UT, US
C Rex Reed
Salt Lake City
UT, US
Richard A Kreifeldt
Sandy
UT, US
Timothy J Shuttleworth
Woodland Hills
CA, US
Agent
Brinks Hofer Gilson & Lione
Assignee
Harman International Industries Incorporated
CA, US
IPC
H03G 3/20
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