These are the test results for my Phonak hearing aid in my right ear: Note: These hearing aids use “Input Compression” or “AGCI” (Automatic Gain Control for inputs). This feature means that the hearing aids vary the amount of amplification according to the loudness of incoming sounds. Soft sounds are amplified more, while loud sounds are amplified less. The complexityof the aids means that they amplify warble sounds used in aided threshold testing differently to running spech. For this reason, aided thresholds measuired with a non-linear aid can only give a general impression about what is audible for complex sounds such as running speech.