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Relationship between listening difficulty and acoustical objective measures in reverberant sound fields
Hayato Sato1, Masayuki Morimoto, Hiroshi Sato
1Environmental Acoustics Laboratory, Graduate School of Engineering, Kobe University, Rokko, Nada, Kobe 657-8501, Japan. hayato@kobe-u.ac.jp
The Journal of the Acoustical Society of America
|April 10, 2008
Summary
Listening difficulty ratings offer a more precise evaluation of speech transmission than traditional intelligibility measures. This study found strong correlations between these ratings and objective acoustic measures like the Speech Transmission Index (STI).
Area of Science:
- Acoustics
- Psychoacoustics
- Speech Perception
Background:
- Previous research established listening difficulty ratings as superior to intelligibility for assessing speech transmission.
- Objective acoustical measures are standard for evaluating speech transmission performance based on room acoustics.
- A detailed investigation into the relationship between listening difficulty and objective measures was lacking.
Purpose of the Study:
- To investigate the correlation between subjective listening difficulty ratings and objective acoustical measures.
- To determine which objective measures best reflect perceived listening difficulty in unidirectional sound fields.
Main Methods:
- Conducted listening tests using 96 impulse responses.
- Analyzed the relationship between subjective listening difficulty ratings and various objective acoustical measures.
- Included measures derived from A-weighted filtered impulse responses (D50, C50, center time) and the Speech Transmission Index (STI).
Main Results:
- The Speech Transmission Index (STI) showed the strongest correlation with listening difficulty ratings among all tested objective measures.
- A-weighted D50, C50, and center time also demonstrated strong correlations with listening difficulty ratings.
- The correlations for A-weighted D50, C50, and center time were not statistically different from the correlation with STI.
Conclusions:
- Listening difficulty ratings provide a sensitive and accurate method for evaluating speech transmission.
- Objective measures, particularly STI and those derived from A-weighted filtered impulse responses, align well with subjective listening difficulty.
- These findings support the use of specific objective measures in room acoustic design to optimize perceived speech clarity.
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