Method and apparatus for distortion product emission testing of hearing

摘要: Apparatus and method are disclosed for the recording of distortion product emission (DPE) levels in human beings. At least one microphone a sound-delivery system is inserted external ear canal manner similar to that required position small hearing aid. Two primary tones T f1 , f2 applied simultaneously ear. The cochlea inner produces DPE tone which sensed by microphone. as function input frequencies f 1 2 . Such frequency equal 2f -f collected 100 Hz steps adjusting maintaining substantially constant ratio between output forms created: an audiogram input/output function. Noise picked up reduced averaging signal many times, yet causing each signals averaged be same phase every other signal. Random noise process. Body may using two microphones applying such plus differential amplifier. less sensitive microphone, after amplification adjustment negative amplifier results with body reduced, but unchanged. This abstract disclosure-is not intended define scope invention.