A phonetic analysis of prenasalized stops in Moru

This study investigates the acoustic properties of prenasalized stops. Theoretical considerations of the acoustic consequences of the articulatory gestures necessary to produce a prenasalized stop are presented. Acoustic analyses with particular emphasis on spectral characteristics tested the validity of the theoretical model. These analyses focussed on the closure interval prior to the release of the oral constriction and on the release. The acoustic properties of initial prenasalized stops were compared to those of initial nasal consonants and voiced oral stop consonants in Moru. The results show that the spectral characteristics of the initial part of the closure interval of prenasalized stops are similar to those of the murmur of the nasal, and the nature of the release of prenasalized stops is similar to that of voiced stops. Prenasalized stops are distinguished from voiced stops and nasals by an amplitude drop of 10-20 dB in the closure interval immediately preceding the release, reflecting the timing of velopharyngeal closure prior to the release of the oral closure. The results are discussed in terms of the phonetic/phonological status of prenasalized stops.