05182774 is referenced by 100 patents and cites 10 patents.

A headset for acoustic reproduction of an electronic signal which electronic signal is representative of the summation of a desired audio signal and an anti-noise signal. The headset includes a headband, an earcup mounted to the headband, a driver mounted within the earcup which receives and acoustically reproduces the electronic signal, a directional microphone which detects and transduces the acoustical pressure within the earcup cavity, means for generating the anti-noise signal from the microphone signal, and a positioning member for mounting the microphone to the earcup in a position so that the microphone is acoustically coupled to the driver. The microphone is oriented so that its vented or open face is pointing towards the driver. If the driver is provided with an inner dome portion and an outer annulus portion the microphone is positioned by its attachment to a grille plate extending across the driver, the microphone being mounted to the grille plate on a side opposite the driver. The grille plate includes a plurality of apertures, at least one of which is positioned proximate the center of the driver with the microphone mounted across that aperture so that the microphone is acoustically coupled to the dome portion and acoustically isolated from the outer annulus portion.

Noise cancellation headset
Application Number
Publication Number
Application Date
July 20, 1990
Publication Date
January 26, 1993
Terrance R Bourk
San Diego
Fredrikson & Byron
Telex Communications
H04M 1/00
H04R 25/00
H04R 1/10
A61F 11/06
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