Measurements of the acoustic effectiveness and quality of trained singers' voices

Having collected physiological data on professional singers, we have the basis to propose neural circuits which effectuate highly qualified voices. We can derive a quality test for stage singers and techniques for training, conserving, and treating the voice. Our method consists of the analysis of swell tones on the vowels /a/ and /ɛ/ in the middle range to obtain (1) the spectral component in the area of 3000 Hz as a measure of the penetrating power of the trained voice in large halls and (2) the parametric characteristics of the vibrato. We suspect that the origin of the vibrate is the consequence of an overload of the control circuit resulting in FM in the m. vocalis in connection with the m. cricothyroid—the controller being synapses in the medulla oblongata. This is similar to the tremor—with a frequency of 8–12 Hz, a slightly higher rate than that for vibrato. We have developed a portable electronic device which indicates (1) the plot of the relative intensity of the singing formant of 3000 Hz and (...