Enhanced Speech Yielding Higher Intelligibility for All Listeners and Environments

The current paper discusses two approaches to enhanced speech in reverberation/noise: machine signal processing and human speech production. We reviewed the speech enhancement techniques, including steady-state suppression and compared the modulation spectra of speech signals before and after processing. We also introduced the Lombard-like effect of speech in reverberation, and compared the characteristics of speech signals, including the modulation spectra between speech signals uttered in quiet and reverberation. We found that the enhanced speech signals have distinct characteristics that yield higher speech intelligibility. Index Terms: speech enhancement, steady-state suppression, modulation spectrum, intelligibility of speech, reverberation, Lombard effect 1