Attempts to determine uniform, objective criteria for assessing human perception and acoustic impact

Abstract

The questions of the acoustic impact on a section of the population and the intelligibility of speech in transmission systems or in room acoustics are being treated in terms of statistics without consideration of the scatter in human perceptiveness. Both the nuisance threshold and the threshold for other kinds of perception differ from person to person and have a relatively wide scatter. Different approaches therefore cannot be extended to other investigations conducted with other parameters. The fidelity index method for music transmission is discussed by analogy with the articulation index method for speech transmission. Because of the scatter in human requirements and sensitivity as regards noise, we discuss the indifference levels and the classification of sensitivity in the categories “sensitive,” “normal,” and “insensitive.” The correlation of the results with those obtained by means of information theory is pointed out.