Patent ID: 7082205
Filing Date: 2006-07-25
Classification: H04R

Abstract:
1. A method to measure and correct or adjust a sound signal presented to an eardrum by means of a hearing aid in its operational position, said hearing aid including at least one microphone, at least one digital signal processing system comprising at least one digital signal processor for transforming an incoming sound into a transformed signal in conformity with a desired transformation function, said hearing aid having at least one receiver, at least one sensing means for sensing the signal appearing in front of the eardrum, and at least one comparison means ( 5 ), said method comprising the steps of: A. establishing a model of an electroacounstic system comprising the ear and the hearing aid, said model simulating the actual sound signal in the ear canal in front of the eardrum, and storing said model in the hearing aid, B. sensing the actual sound signal appearing in front of the eardrum, converting said sound signal into a digital representation and feeding it back to an input of the digital signal processing system, C. comparing said digital representation of said sensed signal with said model in said comparison means and, in case there is a material difference between the sensed signal and the model, generating an error signal for adjusting said model to the actual sound environment in front of the ear-drum, and by further using said error signal to adaptively modify the process in said digital signal processor by minimizing said error signal.