Articulation Reduction by Combined Distortions of Speech Waves
Doug Martin, R. L. Murphy, Albert Meyer · The Journal of the Acoustical Society of America · 1956
Previous investigators have shown that speech waves can undergo any one of a number of severe forms of distortion in low ambient noise levels without serious reduction of word articulation. There are well-known notable exceptions (e.g., center clipping). However, it is not enough to avoid these exceptional forms of distortion. In the study reported here it has been demonstrated that combinations of speech-wave distortions, which individually are quite innocuous with regard to word articulation, can be devastating in their combined effect, even in the absence of serious noise. Four types of speech-wave distortion were studied, individually and in combination, as follows: gross attenuation of high-frequency components, multiple echo, random amplitude modulation, and gross irregularity of response-frequency characteristic. Ambient noise was also a controlled environmental condition in some phases of the investigation.