[The acoustic analysis of mutational "falsetto"]

Set an objectively scientific foundation for name, diagnosis, therapy and assessment of mutational falsetto.

We analyzed the acoustic samples of patients by computer, 15 patients, 12 normal young men, 13 normal young women and 12 normal children were asked to produced comfortable modal vowel/a/ and /i/, sustained 3 seconds. The falsetto /a/ and /i/ were only collected from young men and women. The acoustic parameters were compared between any two groups.

Both vowel /a/ and /i/, the fundamental frequency, highest fundamental frequency and lowest fundamental frequency of patients are closed to young women's (P > 0.05). Jitter percent and pitch perturbation quotient is significantly higher than other groups (P < 0.05). Fundamental frequency variation has no significant difference between groups, but the patients mean is higher than others. Shimmer percent and peak-to-peak amplitude variation of patients' vowel /a/ are distinctly greater than other groups. Amplitude perturbation quotient of vowel /a/ has no significance between groups, but the patients' group is higher than others. Shimmer percent, peak-to-peak amplitude variation and amplitude perturbation of vowel /i/ has no significant difference between most groups, but the results of patients are the biggest. Noise to harmonic ratio of falsetto is the lowest among all groups. Voice turbulence index of the patients and falsetto is lower than that of others. Soft phonation index of patients is higher than other groups and near to falsetto, vowel /i/ is more significant than /a/. The children falsetto and the patients have voice break.

Mutational "falsetto" is not really falsetto, but rather similar to female's voice. To lower fundamental frequency and improve chest resonance is the key of treatment. Both psychotherapy and voice training are important. We can try to use rigid phonation to treat patients.