Relationships among Fundamental Frequency, Vocal Sound Pressure, and Rate of Speaking

Abstract

Twenty males who could control their vocal effort to reach specified soft and loud vocal levels, spanning 30 db., practised and recorded three vowels and three phrases at four levels, ranging from soft to loud. Increments in vocal effort were accompanied by increase in fundamental frequency, the latter shifting upward increasingly with successive steps in sound pressure. The vocal changes that occurred from one level of speaking to another were somewhat specific to the material that was spoken. Phrases that were spoken with different amounts of vocal effort, soft to loud, were spoken at the slowest rate when said softly.