Multichannel compression in the normal ear and as a signal processing algorithm for the hearing impaired

The nature of sensorineural hearing loss (SNHL) indicates that full-range multichannel compression (FRMCC) signal processing will help the hearing-impaired. Our recent studies of speech perception in hearing impaired subjects support the value of FRMCC with at least 8 channels, especially when the signal-to-noise ratio (S/N) is low. Results from other laboratories, however, have been less favorable. The particular acoustic conditions used in these experiments, plus the restricted time subjects have to acclimatize to each signal processing algorithm, seem to account for the differences among studies, but field testing of FRMCC is needed. Developments in digital signal processing (DSP) have made it possible to plan extensive field tests of binaural 8-channel FRMCC. Hearing-aid users will be able to evaluate the FRMCC in all the acoustic environments they normally encounter, both during and after full acclimatization to the signal processing