In view of its bearing on the design of ground noise reduction systems, a study was undertaken, to determine how sudden or rapid are the increases in amplitude of the speech sounds that must be recorded in dialogue. A large number of oscillograms were taken, a number of which are reproduced herewith. The most important observation is that the human voice can start several of the vowel sounds in such a way that the first wave is from 40 to 80 percent of the final amplitude, or in other words with a suddenness comparable to that of keying an oscillator, but this is rare, being for all practical purposes confined to a few of the more open vowel sounds, when not preceded by any consonant, and only true of certain individuals, and depending on the manner of releasing the breath. Progressive build-up at rates which would carry the modulation from zero to 100 percent in 0.05 second are frequent, while the great majority of syllables start more gradually than this.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.