Evaluating the Strength and Duration of Reverberation and its Influence on Speech Intelligibility

School Name

Dutch Fork High School

Grade Level

11th Grade

Presentation Topic

Physics

Presentation Type

Non-Mentored

Written Paper Award

2nd Place

Abstract

Verbal communication plays a key role in education and its efficacy depends fundamentally on the acoustics of a classroom. The room needs to have a strong reverberation to amplify the speaker’s voice and a short reverberation decay time to avoid loss of clarity. Therefore, developing quantitative methods to evaluate a room’s acoustics is valuable. This project studied and developed techniques for measuring reverberant sound intensity and decay time as a way of comparing the acoustics of various rooms. Additionally, blind listening tests were conducted on human subjects to determine the correlation between the acoustical environment and speech intelligibility. Three rooms with different acoustics were compared. The first experiment studied how reverberation affected the inverse-square relationship between sound intensity and distance. This provided a measure of the absorption of each room. The second experiment measured the duration of reverberation using oscilloscope and audio recording softwares. These experiments showed what conditions provided strong reverberation along with a short reverberation decay time. The final experiment conducted blind listening tests on human subjects to determine their ability to distinguish different phonemes of speech. This experiment confirmed the expectation that the right kind of reverberation, strong but short, is most beneficial for clearly understanding speech. The results of this project are highly relevant to the designs of classrooms and impact the ability of students to effectively understand an instructor.

Location

Founders Hall 210 B

Start Date

3-30-2019 10:00 AM

Presentation Format

Oral and Written

Group Project

No

COinS
 
Mar 30th, 10:00 AM

Evaluating the Strength and Duration of Reverberation and its Influence on Speech Intelligibility

Founders Hall 210 B

Verbal communication plays a key role in education and its efficacy depends fundamentally on the acoustics of a classroom. The room needs to have a strong reverberation to amplify the speaker’s voice and a short reverberation decay time to avoid loss of clarity. Therefore, developing quantitative methods to evaluate a room’s acoustics is valuable. This project studied and developed techniques for measuring reverberant sound intensity and decay time as a way of comparing the acoustics of various rooms. Additionally, blind listening tests were conducted on human subjects to determine the correlation between the acoustical environment and speech intelligibility. Three rooms with different acoustics were compared. The first experiment studied how reverberation affected the inverse-square relationship between sound intensity and distance. This provided a measure of the absorption of each room. The second experiment measured the duration of reverberation using oscilloscope and audio recording softwares. These experiments showed what conditions provided strong reverberation along with a short reverberation decay time. The final experiment conducted blind listening tests on human subjects to determine their ability to distinguish different phonemes of speech. This experiment confirmed the expectation that the right kind of reverberation, strong but short, is most beneficial for clearly understanding speech. The results of this project are highly relevant to the designs of classrooms and impact the ability of students to effectively understand an instructor.