# US 2026/0100181 A1 · Active damping of resonant canal modes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2026/0100181 A1 - Document ID: US20260100181A1 - Status: Published application - Kind: A1 - Application number: 19/355,167 - Filed: 2025-10-10 - Published: 2026-04-09 - Earliest claimed: 2022-09-02 - Assignees: Bose Corporation - Applicants: Bose Corporation - Inventors: John Allen Rule; David J. Warkentin - Web page: https://patentgrep.com/patent/US20260100181A1 ## CPC - G10K 11/17817: {between the output signals and the error signals, i.e. secondary path} - G10K 11/17825: {Error signals} - G10K 11/17823: {Reference signals, e.g. ambient acoustic environment} - G10K 11/17853: {of the filter} - G10K 11/17854: {the filter being an adaptive filter} - G10K 11/17881: {the reference signal being an acoustic signal, e.g. recorded with a microphone} - H04R 1/1083: {Reduction of ambient noise (active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06)} - G10K 2210/1081: Earphones, e.g. for telephones, ear protectors or headsets - G10K 2210/3026: Feedback - G10K 2210/3027: Feedforward - G10K 2210/3028: Filtering, e.g. Kalman filters or special analogue or digital filters - H04R 2460/01: Hearing devices using active noise cancellation - G10K: SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract An active noise reduction (ANR) device includes an acoustic transducer, a first sensor, and a second sensor. The acoustic transducer is configured to generate output audio. The first sensor is configured to capture audio originating from an external environment of the ANR device. The second sensor is configured to generate a signal indicative of (1) the audio originating from the external environment and (2) the output audio generated by the acoustic transducer. The output audio generated by the acoustic transducer is modified based on a portion of the signal generated by the second sensor, the portion being attributable to a resonant mode of a user's ear canal. ## Claims ### Claim at position 1 -30. (canceled) ### Claim 31 An active noise reduction (ANR) device comprising: an acoustic transducer configured to generate output audio; a first sensor configured to generate a first signal indicative of audio originating from an external environment of the ANR device; a second sensor configured to generate a second signal indicative of audio arriving at an ear canal of a user of the ANR device; and circuitry configured to: identify, based on the first signal and the second signal, a signal indicative of one or more resonant modes of the user's ear canal; and modify the output audio generated by the acoustic transducer based on the signal indicative of the one or more resonant modes of the user's ear canal. ### Claim 32 (depends on 31) The ANR device of claim 31, wherein the second signal indicative of the audio arriving at the user's ear canal comprises the audio originating from the external environment, and the output audio generated by the acoustic transducer. ### Claim 33 (depends on 31) The ANR device of claim 31, wherein the second sensor is disposed closer to the user's ear canal than the first sensor. ### Claim 34 (depends on 31) The ANR device of claim 31, wherein the signal indicative of the one or more resonant modes of the user's ear canal comprises: a first portion derived from the audio originating from the external environment of the ANR device, and a second portion derived from the output audio generated by the acoustic transducer. ### Claim 35 (depends on 31) The ANR device of claim 31, wherein at least one of the one or more resonant modes corresponds to a resonant frequency between 3 kHz and 10 KHz. ### Claim 36 (depends on 31) The ANR device of claim 31, wherein the circuitry is configured to modify the output audio to damp at least a portion of the signal indicative of the one or more resonant modes of the user's ear canal. ### Claim 37 (depends on 31) The ANR device of claim 31, wherein the output audio is modified by summing, with the output audio, a signal indicative of a velocity of the one or more resonant modes. ### Claim 38 (depends on 37) The ANR device of claim 37, wherein the signal indicative of the velocity of the one or more resonant modes represents a multiple of the velocity of the one or more resonant modes. ### Claim 39 (depends on 37) The ANR device of claim 37, wherein the signal indicative of the velocity of the one or more resonant modes represents a filtered version of the signal generated by the second sensor. ### Claim 40 (depends on 31) The ANR device of claim 31, wherein the ANR device is configured to be inserted, at least partially, in an ear of the user. ### Claim 41 (depends on 31) The ANR device of claim 31, wherein the circuitry is configured to modify the output audio generated by the acoustic transducer to attenuate, at a resonant frequency corresponding to at least one of the one or more resonant modes, the audio originating from the external environment of the ANR device that arrives at the user's ear canal. ### Claim 42 (depends on 31) The ANR device of claim 31, wherein the circuitry is configured to modify the output audio generated by the acoustic transducer to smooth, at a resonant frequency corresponding to at least one of the one or more resonant modes, a transfer function representing the user's ear canal. ### Claim 43 (depends on 31) The ANR device of claim 31, wherein the circuitry is configured to modify the output audio generated by the acoustic transducer using broadband noise reduction at a plurality of frequencies below 2 kHz. ### Claim 44 (depends on 31) The ANR device of claim 31, the signal indicative of the one or more resonant modes of the user's ear canal is identified by accounting for an individualized ear canal response of the user. ### Claim 45 (depends on 31) The ANR device of claim 31, wherein one or more resonant frequencies corresponding to the one or more resonant modes are identified using at least one of a phase-locked loop or a peak detection algorithm. ### Claim 46 (depends on 31) The ANR device of claim 31, wherein one or more resonant frequencies corresponding to the one or more resonant modes are tracked in real time. ### Claim 47 A method comprising: receiving, from a first sensor of an active noise reduction (ANR) device, a first signal indicative of audio originating from an external environment of the ANR device; receiving, from a second sensor of the ANR device, a second signal indicative of audio arriving at an ear canal of a user of the ANR device identifying, based on the first signal and the second signal, a signal indicative of one or more resonant modes of the user's ear canal; and modifying output audio generated by an acoustic transducer based on the signal indicative of the one or more resonant modes of the user's ear canal. ### Claim 48 (depends on 47) The method of claim 47, wherein the second signal indicative of the audio arriving at the user's ear canal comprises the audio originating from the external environment and the output audio generated by the acoustic transducer, and wherein identifying the signal indicative of the one or more resonant modes of the user's ear canal comprises: deriving, from the audio originating from the environment external to the ANR device, a first portion that is attributable to the one or more resonant modes of the user's ear canal; deriving, from the output audio generated by the acoustic transducer, a second portion that is attributable to the one or more resonant modes of the user's ear canal; and combining the first portion and the second portion. ### Claim 49 (depends on 47) The method of claim 47, wherein modifying the output audio generated by the acoustic transducer comprises damping at least a portion of the signal indicative of the one or more resonant modes of the user's ear canal. ### Claim 50 One or more machine-readable storage devices having encoded thereon computer readable instructions for causing one or more processing devices to perform operations comprising: receiving, from a first sensor of an active noise reduction (ANR) device, a first signal indicative of audio originating from an external environment of the ANR device; receiving, from a second sensor of the ANR device, a second signal indicative of audio arriving at an ear canal of a user of the ANR device identifying, based on the first signal and the second signal, a signal indicative of one or more resonant modes of the user's ear canal; and modifying output audio generated by an acoustic transducer based on the signal indicative of the one or more resonant modes of the user's ear canal.