Enhancement of Speech Intelligibility at High Noise Levels by Filtering and Clipping

Experiments are described in which the intelligibilities of preprocessed and normal speech are compared when a high level of ambient noise exists at the listener's ears. Preprocessing involves removal of the first formant of the speech prior to infinite amplitude clipping. The resulting clipped speech is highly intelligible; under high noise conditions its intelligibility is considerably greater than that of normal speech at a comparable average sound level.