It should be possible to carry out dynamic range compression in hearing
devices, and in particular in hearing aids, so it is free from distortion
and practically in real time. For this purpose it is proposed that the
modulation spectrum be obtained from the audio or input signal. The
modulation spectrum is subsequently directly modified corresponding to a
predefined compression function. Finally a modified or compressed output
signal is recovered from the modified modulation spectrum. Alternatively
a complex envelope may be obtained from the input signal, which is
filtered using time-variant modulation filtering corresponding to a
predefined compression rule. A distortion-free, compressed output signal
may also be recovered herefrom.