The Effect of Room Acoustics and Sound-Field Amplification on Word Recognition Performance in Young Adult Listeners in Suboptimal Listening Conditions

Abstract

To compare the speech recognition performance of young adult listeners with normal hearing in 2 college classrooms, only 1 of which met American National Standards Institute (ANSI) S12.60-2002 acoustic standards. Also, differences in speech recognition performance were compared in both classrooms with and without the use of a classroom amplification system. The speech was presented at low intensity to simulate listening in the rear seats of a large college classroom. Listeners were randomly assigned seats in the 2 classrooms, and Northwestern University Auditory Test No. 6 (NU-6) words were presented via a loudspeaker from the front of the classroom for all listening conditions as well as through a sound-field infrared system with ceiling-mounted speakers during the amplified condition. Results showed statistically significant differences in speech recognition performance between classrooms, with and without classroom amplification, and across the rows of each classroom when the classroom amplification system was not used. These results demonstrate how meeting the ANSI S12.60-2002 standard, which was written for elementary school classrooms, can benefit young adult listeners in postsecondary classrooms. Also, classroom amplification was shown to improve speech recognition for students across the classroom in both acoustically poor and acoustically sound classroom environments.