Patent ID: 8571228
Filing Date: 2013-10-29
Classification: G10K,H04R

Abstract:
1. An earpiece of an ANR device comprising: a casing defining a front cavity having an opening; a ear coupling disposed about the opening and having a passage formed through the ear coupling, the ear coupling being structured to engage a portion of the head of a user of the ANR device to acoustically couple the front cavity through the opening and the passage to an ear canal of an ear of the user, and the ear coupling being structured to engage the portion of the head of the user to form at least a partial seal between the ear coupling and the portion of the head of the user to provide passive noise reduction that limits entry of noise sounds emanating from an environment external to the casing into at least the ear canal; an acoustic driver disposed within the casing to acoustically output sounds into the front cavity to be conveyed through the opening and the passage to the ear canal; a feedback microphone disposed within the front cavity to detect noise sounds present within at least the front cavity to enable the provision of feedback-based ANR; a feedforward microphone carried by the casing and acoustically coupled to the environment external to the casing to enable the provision of feedforward-based ANR; and a leak aperture formed in the casing to couple the front cavity to the environment external to the casing to reduce variability in the passive noise reduction arising from variability in the at least a partial seal between the ear coupling and the portion of the head, wherein the casing further defines another cavity having a cavity opening coupling the another cavity to the environment external to the casing; the earpiece further comprises a cavity cover structured to close the cavity opening with a leaky closure by which the another cavity remains at least acoustically coupled to the environment external to the casing; and the leak aperture couples the front cavity to the environment external to the casing indirectly through the another cavity and through the leaky closure by which the cavity cover closes the cavity opening, wherein: the passive noise reduction provided by engagement of the ear coupling to the portion of the head of the user is effective against higher audible frequency noise sounds emanating from the environment external to the casing; the provision of the feedforward-based ANR enabled by the feedforward microphone is effective against midrange audible frequency noise sounds emanating from the environment external to the casing; and the provision of the feedback-based ANR enabled by the feedback microphone is effective against lower audible frequency noise sounds emanating from the environment external to the casing.