System for controlling a transfer function of a hearing aid

A system for controlling gain function of a hearing aid, and comprising a microphone adapted to convert a sound pressure to an input signal, a speaker adapted to convert an output signal to a processed sound pressure, a signal processing means interconnecting said microphone and said speaker and adapted to process said input signal to said output signal according to a control signal, and a signal analysis means connecting to said microphone and to said signal processing means, and wherein said signal analysis means comprises a first signal path having first detector means adapted for maximum level and squelch level detection and a second signal path having second detector means adapted for compression level detection and a controller means adapted to generate said control signal based on said first and second detector means responses to said input signal.