Fitting a sound processing device for an individual is automated using a computer. Fitting and customization is carried out using natural sounds without specialized audiometric equipment or audiological expertise. Software for this purpose is downloaded from an internet portal. The computer plays back acoustic signals, and obtains user input reflecting the user's perceptions of the acoustic signals, from which a hearing map is derived, representing the user's hearing. An algorithm updates the device fitting based on the hearing map. Also provided is pre-sale virtual device fitting, whereby a virtual signal processing path is established in the computer, reflecting a signal processing function of a sound processing device of interest to the user. An algorithm updates parameters of the virtual processing path, based on the hearing map. Audio signals passed through the virtual processing path are played back to the user, giving the user an acoustic indication of future device performance.