Christopher Edward Welsh

US Patent:

8107652, Jan 31, 2012

Filed:

Aug 4, 2008

Appl. No.:

12/221644

Inventors:

Medford Alan Dyer - San Diego CA, US
Christopher Todd Welsh - Fishers IN, US
Jeffrey Phillip McAteer - Carmel IN, US
Alan Dean Michel - Fishers IN, US

Assignee:

MWM Mobile Products, LLC - Indianapolis IN

International Classification:

H04R 11/04

US Classification:

381191, 381174, 381355, 381369

Abstract:

An omnidirectional electret condenser microphone element with improved low frequency background ambient acoustical noise rejection is provided. The omnidirectional electret condenser microphone element includes a plurality of passageways in acoustic series that couple at least one acoustic aperture of the microphone element to an acoustic cavity formed within the microphone element. At least one of said plurality of passageways is of a predefined size that is determined to provide the desired response roll-off within a predefined frequency range. In at least one preferred configuration, the roll-off resulting from the plurality of passageways is greater than 2. 0 dB between 300 and 100 Hz. In at least one alternate preferred configuration, the roll-off resulting from the plurality of passageways is greater than 3. 0 dB between 300 and 100 Hz.