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Published on: January 23, 2017
The loudness of sounds whose spectra differ at the two ears
Brian R Glasberg1, Brian C J Moore
1Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, England.
The Journal of the Acoustical Society of America
|April 8, 2010
Summary
The Moore and Glasberg loudness model accurately predicted dichotic sound data, except when spectral bands were presented to different ears. A revised experiment using the ERB(N)-number scale confirmed the model's predictions.
Area of Science:
- Psychoacoustics
- Auditory perception
- Sound intensity modeling
Background:
- The Moore and Glasberg (2007) model accurately predicts dichotic sound loudness.
- Discrepancies were observed with Zwicker and Zwicker's (1991) experiment using non-overlapping spectral bands presented to different ears.
Purpose of the Study:
- To investigate the Moore and Glasberg model's predictions for dichotic sounds with non-overlapping spectra.
- To reconcile discrepancies between the model and previous experimental findings.
Main Methods:
- Noise stimuli were filtered into 24 bands (1 bark wide) and grouped into composite bands (1, 2, 4, or 12 sub-bands).
- Composite bands were presented dichotically (to different ears).
- Bandwidths were based on the Equivalent Rectangular Bandwidth (ERB)-number scale, and loudness matching was used.
Main Results:
- Loudness estimates increased as the number of composite bands increased and their spacing decreased.
- This pattern aligned with the Moore and Glasberg model's predictions, contrary to the earlier Zwicker and Zwicker experiment.
Conclusions:
- The revised experimental approach, using the ERB(N)-number scale and loudness matching, validated the Moore and Glasberg loudness model for dichotic stimuli.
- The model's predictions are consistent with auditory perception when spectral components are presented to separate ears.
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