Intraspeaker variability on nasal consonant [m]

Our previous study determined that intraspeaker variability is small for the first formant of the nasal/m/when read in a carrier sentence and larger when read in a paragraph. This study investigates factors responsible for increase in intraspeaker variability. Syllables [mi], [ma], and [mu] were each read ten times and recorded (1) in a carrier sentence with a slow rate, (2) in a carrier sentence with rapid rate, and (3) in a paragraph with normal reading rate. First formant frequency contours were compared to determine effects of context and rate on intraspeaker variability. Findings suggest that intraspeaker variability of the nasal /m/ is closely related to context, but rate of utterance is somewhat unimportant. The implication is that, although the /m/ is produced within a vocal tract that remains relatively constant, it is still subject to some variation due to the effects of coarticulation. A comprehensive study of the sounds subject to the least coarticulatory effects may prove to be important in speaker identification.