22/12/2025
"Stated simply, the phenomenon seems to be that a greater subglottic pressure will result in a higher fundamental frequency. Although this is certainly an accurate deduction, it is not in agreement with known behavior of simple mechanical vibrating systems. In a linear mechanical vi****or or acoustical resonator, for example, an increase in driving force will increase the amplitude of the response, but not the frequency. Internal elastic and inertial properties, such as stiffness and mass, determine the vibrational frequency. We would be quite annoyed if a piano string, or organ pipe, were to increase its fundamental frequency substantially whenever it is struck or blown harder. Yet a toy ukulele strung with rubber bands has, in fact, such an annoying characteristic. So also does a New Year’s Eve noisemaker."
from "What Physical Factors are Involved in the Relationship Between Vocal Pitch and Breath Support?" by Dr. Ingo Titze, Journal of Singing, Jan/Feb 1981, pp. 37
