Audio signal processing method and system for correcting a spectral shape of a voice signal measured by a sensor in an ear canal of a user

An audio system comprising at least an internal sensor, wherein the internal sensor corresponds to an air conduction sensor to be located in an ear canal of a user of the audio system and arranged to measure acoustic signals which propagate internally to a head of the user, wherein the internal sensor is configured to produce an internal audio signal, wherein said audio system further comprises a processing circuit configured to:

• determine an audio spectrum of the internal audio signal,
• determine a spectral center of the audio spectrum,
• determine a spectrum shape correction filter based on the spectral center,
• filter the internal audio signal by using the spectrum shape correction filter, thereby producing a filtered internal audio signal.

A non-transitory computer readable medium comprising computer readable code to be executed by an audio system comprising at least an internal sensor, wherein the internal sensor corresponds to an air conduction sensor to be located in an ear canal of a user of the audio system and arranged to measure acoustic signals which propagate internally to a head of the user, wherein said audio system further comprises a processing circuit, wherein said computer readable code causes said audio system to:

• produce an internal audio signal by the internal sensor,
• determine an audio spectrum of the internal audio signal,
• determine a spectral center of the audio spectrum,
• determine a spectrum shape correction filter based on the spectral center,
• filter the internal audio signal by using the spectrum shape correction filter, thereby producing a filtered internal audio signal.