A method of determining an audio controller for a headphone that is configured to use an acoustic transducer to develop sound that is delivered to an ear of a user and that includes a feedback microphone that is configured to sense sound developed by the acoustic transducer, and a related computer program product and system. A first audio transfer function between the acoustic transducer and the feedback microphone is measured. A second audio transfer function between the acoustic transducer and the feedback microphone with a feedback controller applied is determined. The audio controller is calculated based on both the first audio transfer function and the second audio transfer function.