1. For use with a auditory prothesis having acoustic parameters which at least in part determine at least one of the auditory characteristics of said auditory prosthesis, said acoustic parameters being adjustable, a method of determining said acoustic parameters of said auditory prosthesis which will provide a user of said auditory prosthesis with a target auditory response, comprising the steps of: determining said target auditory response of said user; determining said auditory characteristics of said auditory prosthesis operating in conjunction with said user and based upon a software model ; and optimizing said acoustic parameters of said auditory prosthesis by comparing the auditory response of said auditory characteristics with said target auditory response and by adjusting said acoustic parameters to minimize the error of said comparison.