On phonetic characteristics of pause in the Korean read speech

To guarantee a good quality of synthesized speech in a rule-based synthesis, detailed and accurate segmental and suprasegmental rules for a given text are necessary. Especially, much work on the prosodic structure is needed. The goal of this study is to examine roles of syntactic information, intonation pattern, and phrase final lengthening in formation of prosodic units or perception of a phrase boundary. It investigates (a) whether location of (perceived) pause or a phrase boundary, one of the phonetic aspects of prosody, is syntactically determined and (b) how phonetic features such as a silence interval, intonation pattern, and lengthened vowel duration interacts with one another in formation of prosodic units. Radio news of two male announcers were recorded. Perception test of a phrase boundary was performed on the recorded data and at the same time both syntactic and acoustic analyses of them were done. The results showed that perceived pause were accompanied by at least one of the three phonetic features. Many cases were observed where the major syntactic boundary was not accompanied by any of the three phonetic features indicating that syntactic information does not play a crucial role in defining prosodic units. Rather, intonation pattern was proved to play a crucial role in formation of prosodic units.