Acoustic properties of certain VCC utterances.

Abstract

Acoustic properties of certain VCC utterances were investigated by means of spectrographic analysis. The speech stimuli consisted of the consonant clusters /-sp, -st, -sk/ in combination with the vowels /i e æ ɑ o u/ spoken by ten adult male speakers of American English. Measurements were made of the duration of silent interval and burst frequency of the plosives, the lower cutoff frequency and transitional frequency of the fricative, and the frequencies and transitions of the vowel formants. The effects of coarticulation of each of the phonetic segments on the others was a particular interest. The results were compared to those of earlier studies employing similar stimuli synthetically produced. It was found that the period of silent interval was on the average 13 greater for /p/ as compared to /t/ and /k/. The frequency of the plosive bursts occurred in three distinct regions: /t/ in the higher, /p/ in the lower, and /k/ in the intermediate region on the frequency scale. The lower cutoff frequency of /s/ was strongly influenced by the nature of the preceding vowel; a much lower value occurred following rounded vowels. Final plosives seemed to have little influence on the lower cutoff frequency of /s/. There was a strong falling transition in /s/ before /p/; no significant transition was found in /s/ before /t/ or /k/. F2 locus of /s/ was found at about 1400 Hz; no such unique F1 locus of /s/ was indicated.