Patent ID: 7048692

Claim:
A method for estimating the shape of an auditory filter by finding a coefficient p of a roex (p, r) filter which is used as a model for the shape of the auditory filter, comprising the steps of: determining a threshold masking level N x based on a tone S which adds a given value x to a threshold of hearing T of a subject in frequency f; generating a tone S′ which subtracts a given value a from the tone S; generating a masker of notch width g and a level N x including the frequency f in a notch; transmitting to the subject an inspection sound which superposes the masker on the tone S′; measuring a minimum notch width g x−a of the subject while varying the notch width g; estimating an upper limit value g max of the notch width g suitable for the subject from the minimum notch width g x−a ; calculating the coefficient p from the upper limit value g max , the minimum notch width g x−a , the value x corresponding to a coefficient r, and a value a; and estimating the shape of the auditory filter from the coefficient p calculated above and the value x corresponding to the coefficient r.