An improved hearing aid, and processes for adaptively processing signals therein
to improve the perception of desired sounds by a user thereof. In one broad aspect,
the present invention relates to a process in which one or more signal processing
methods are applied to frequency band signals derived from an input digital signal.
The level of each frequency band signal is computed and compared to at least one
plurality of threshold values to determine which signal processing schemes are
to be applied. In one embodiment of the invention, each plurality of threshold
values to which levels of the frequency band signals are compared, is derived from
a speech-shaped spectrum. Additional measures such as amplitude modulation or a
signal index may also be employed and compared to corresponding threshold values
in the determination.
