The present invention relates to a listening device for a hearing impaired person. The present invention furthermore relates to a corresponding operating method of operating a listening device and to a corresponding computer program. In particular, the present invention relates to a listening device that comprises a signal processing unit that is controlled by a controller configured to implement a combined feed-forward and feed-back control in order to ensure that both an electric input signal and a processed electric output signal have at least almost identical modulation index values. Thereby, speech intelligibility is increased, in particular for a hearing impaired person being capable of perceiving sound pressure levels in a substantially decreased dynamic range.