Auralizations and other computer model studies to predict qualitative and quantitative measures of speech intelligibility in classrooms

Abstract

Auralizations and other computer model studies were used to predict qualitative and quantitative measures of speech intelligibility in classrooms under realistic conditions of background noise and reverberation. Speech intelligibility tests were given to college students in two classrooms and one racquetball court at 5 signal-to-noise ratios. Auralizations of the speech intelligibility tests were made from computer. Speech intelligibility tests were then administered in a sound booth using the auralized material. Fifteen different acoustical measurements related to speech intelligibility were also made at multiple locations in the actual classrooms and in the computer models of the classrooms. The scores on the speech intelligibility tests given in the actual rooms in the five noise conditions were closely duplicated in the equivalent tests conducted in a sound booth using the simulated speech signals obtained in the computer models. Both quantitative and qualitative measures of speech intelligibility in the actual rooms were accurately predicted in the computer models. Correlations (R2) between acoustical measures made in the full size classrooms and the computer models of the classrooms of 0.92 to 0.99 were found.