Acoustic features of pharyngeal /s/ fricatives produced by speakers with cleft palate.

Acoustic features of pharyngeal /s/ substitutions spoken by persons with cleft palate were measured using digital computer processing and analysis techniques. Average short-time spectral characteristics of pharyngeal /s/ sounds produced by four speakers with cleft palate were compared with spectral features of normally gestured /s/ sounds spoken by two normal speakers. The output spectral characterized by a set of distinctive acoustic properties that differed markedly from normal /s/ sounds gestured in the front of the mouth. One consistent feature of pharyngeal /s/'s was the presence of multiple spectral maxima. Pharyngealization of /s/ consonants gave rise to spectral outputs with energy maxima appropriate to high F1 values which were relatively close to F2, as well as to relatively strong, low frequency excitation of F2 speakers with cleft palate were, in general, comparable to those of /h/ fricatives spoken by speakers of Arabic.