The assessment of speech intelligibility  by the coefficient of inter ear correlation  speech signal

This article analyzes the possibility of evaluating the intelligibility of speech in terms of the coefficient of interaural correlation. The idea of using a speech program for objectively assessing the intelligibility of speech in the prem ises is substantiated. A comparison is made of the subjective and objectivized evaluation of the intelligibility of the speech with the estimation by means of the coefficient of the correlation obtained on the basis of measurements binaural signals in the locations of listeners. Today, there is a significant amount of objective methods for assessing the readability of speech in rooms and acoustic paths. In all these methods, the role of the test signal uses broadband noise. As practice shows, despite the sufficient set of auditory frequencies, broadband noise has significant differences from the language human perception. 

Unlike noise, the speech signal has a more complex structure. The physical basis of speech is the acoustic oscillations of air jet, which are formed by the organs of articulation. However, not only the acoustics of sounding determines how a person hears the tongue. The phonetic language system has a decisive influence on the mechanisms and the result of speech perception. Hence - errors in the perception of oral speech in different situations of communication, if the general context of this language does not allow unequivocally restore its verbal composition.  

The main parameters of language quality are considered to be component and phrasal legibility of the language, the quality of the language in comparison with the quality of the language of the reference path and the quality of speech in real working conditions. Exploring and estimating such parameters with broadband noise is quite difficult, since when using it, we have no phrases or syllables. Consequently, for a more reliable objective assessment of legibility of speech it is expedient to use a speech signal. The purpose of the article is to investigate the possibility of using interaural correlation obtained by measuring binaural speech signals, in order to assess the readability of the language in the room. 

In order to assess the readability of speech in the hall, it is possible to use the values of the interaural correlation obtained by measuring binaural signals in listening places.

By comparing the results of articulation tests in the room with the values of the coefficients between the ear correlations, one can establish a scale of IASS values that accord to a certain degree of intelligible speech.