Vocal tract dimensional characteristics of professional female singers with different types of singing voices

This study investigated the relationship between the female singers´ singing voice classification and their vocal tract length, volume, and vowel formant frequencies. Acoustic pharyngometer (ART) was used to measure the vocal tract length and volume of Twenty-seven sopranos, and Twenty-three mezzo-sopranos. The first three formant frequencies of vowels produced by these singers were also obtained. Results showed that sopranos had shorter oral and vocal tract length, smaller oral and vocal tract volume than mezzo-sopranos significantly. Sopranos had higher first three and averaged first three vowel formant frequencies than mezzo-sopranos generally. These preliminary findings indicated that, besides vocal tract length, vocal tract volume may also affect the formant frequencies of the singers, and thus the classification of different types of singing voices.