Estimation of the Subjective Intelligibility With Superimposition of BN8 in the Environment of the Orthodox Church Built in the Moravian Style

In this paper, the estimation of subjective intelligibility in the presence of Babble noise BN8, for certain SNR values, in the ambiance of an Orthodox church, is presented. The first part of the paper describes estimation algorithms for objective and subjective speech intelligibility in enclosed spaces. Following that, as a result of analyzing the relationship between subjective and objective intelligibility, the Subjective Intelligibility Estimation (SIE) Parameter β, was defined. In the second part of the paper, an experiment is described in which the intelligibility is analyzed in the environment of the Orthodox church built in the Moravian style. The analysis is based on testing the intelligibility of words created by convolving Room Impulse Responses (RIRs) with clean speech. Intelligibility was tested using objective and subjective methods, and, in that way, objective and subjective acoustic parameters: a) Speech Transmission Index, STI, b) Articulation Loss of Consonants, Al <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cons</inf> , and c) subjective intelligibility, SI, were determined. The results are presented graphically and in tables. The estimation of speech intelligibility quality was determined through a comparative analysis of objective and subjective parameters with the Standard IEC 60268-16 values. The SIE parameter β was calculated for SNR = -10, …, 50 dB and, after that, the mean value β (SNR)̄ was calculated. Finally, by applying the numerical method of least squares, the Estimation Parameter β <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a</inf> (SNR) was calculated.