Acoustic characteristics of the metallic voice quality

Purpose: To characterize the fundamental frequency and the frequency of the formants F1, F2, F3, and F4 from vocal emissions of amateur singers with metallic voice quality. Methods: There were 60 amateur female singers aged between 18 and 60 years old; 30 women with metallic voice quality forming the study group (SG) and 30 women without such a vocal quality forming control group (CG). The sample was selected through voice screening confirmed by reviewers after reaching a consensus. Regarding data collection, sustained vowel emissions in usual tone and at two predetermined frequencies, by which the values of F-0 and frequency of the formants F1, F2, F3, and F4 were obtained, were recorded and analyzed. Results: Comparing the emissions in usual tone, no difference for F-0 was found, but the values of the formants F2, F3, and F4 were higher in the SG. In the preestablished tones, there was a difference between the two groups in the formants F3 and F4 for both tones. Conclusion: It is possible to characterize metallic voice quality as a normal fundamental frequency, with increasing frequency of the F2 formant, and values of frequencies of formants F2, F3, and F4 higher when compared to the CG.