Sonorant-fricative clusters in English

Several phonologists have claimed that the insertion of a stop between a sonorant and a fricative consonant in syllable final sonorant-fricative consonant clusters follows from universal constraints on the human speech production and perception mechanism. In our experiment five speakers each of American and South African English read a list of real and nonsense words ending in clusters of [n] or [l] plus [s] or [ts] and their voiced counterparts. The duration of the stressed vowel and each measurable cluster segment was measured from spectrograms. Preliminary results suggest that (1) South African speakers maintain the contrast between sonorant-fricative and sonorant-stop-fricative clusters (tense versus tents) yet keep total syllable duration constant. (2) Voicing of the final fricative (tens) blocks the insertion of the stop in the speech of the American speakers, while (3) those speakers who insert a stop before /s/ (neutralizing /ns/ and /nts/) lengthen the total duration of the syllable. Results imply that stop insertion is a language specific process that can be implemented in several ways.