US Patent 8027481 Personal hearing control system and method

A personal hearing control system includes a microphone located within a user's sealed ear canal, a speaker having a diaphragm which directs sound into the ear canal, and a controller which drives the speaker such that the system emulates the acoustics of the user's open ear canal. Also provided are a microphone located on the outer ear side of the sealed ear canal, which is coupled to a handheld interface unit having multiple inputs and operating modes. A user-selected input is processed by the interface unit, and the processed signal is coupled to the speaker. In one operating mode, the output of the outer ear mic is processed so as to cancel sound that leaks from the outer ear to the inner ear side of the seal.