Synthetic speech intelligibility under several experimental conditions

Abstract

Present technology makes it possible for nonspeaking individuals to communicate using electronic augmentative communication devices that generate synthetic speech. For augmented individuals to communicate effectively, the synthetic speech must be intelligible, not just in ideal listening conditions, but in the presence of background noise. The present study sought to determine the extent to which two of the most frequently researched DECTalk™ voices, DECPaul and DECBetty, degraded in the presence of background noise at a signal-tonoise (S/N) ratio of +10 dB. It further sought to determine the effect of adding visual cuing to synthetic speech output on the intelligibility of DECTalk. The results suggested that DECTalk is significantly less intelligible in the presence of background noise at a +10 dB S/N ratio than in ideal listening conditions. Although the addition of visual cuing did not increase intelligibility overall, subjects did have fewer sentence errors when visual cuing was added to synthetic speech output in the presence of background noise. The implications of these findings and the need for further research are discussed.

• augmented individual
• communication partner
• intelligibility
• signal-to-noise (S/N) ratio
• text-to-speech synthesis