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Updated: May 9, 2026
08:34
The Measurement and Treatment of Suppression in Amblyopia
Published on: December 14, 2012
Effect of spectral overlap on the echo suppression threshold for single reflection conditions
Andreas Walther1, Philip Robinson, Olli Santala
1Audiovisual Communications Laboratory, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland. andreas.walther@epfl.ch
The Journal of the Acoustical Society of America
|August 10, 2013
Summary
Spectral differences between direct and reflected sound impact echo perception. This study reveals how filtering sound frequencies affects the echo suppression threshold in performance venues.
Area of Science:
- Acoustics
- Psychoacoustics
- Architectural Acoustics
Background:
- Sound spectra at a receiver in performance venues are altered by factors like seat dip effect, surface diffusion/absorption, and source directivity.
- Understanding the interplay between direct and reflected sound is crucial for designing acoustically pleasing spaces.
Purpose of the Study:
- To investigate how variations in the spectral content of direct and reflected sound influence the echo suppression threshold.
- To quantify the relationship between frequency filtering and the perception of echoes.
Main Methods:
- Simulating acoustic conditions in performance venues.
- Analyzing the spectral differences between direct and reflected sound signals.
- Measuring the echo suppression threshold under controlled spectral conditions, including high-pass filtering.
Main Results:
- For high-pass filtered direct sound with broadband reflections, initial low-frequency attenuation increased the echo suppression threshold.
- Higher cutoff frequencies for the direct sound led to a drastic decrease in the echo suppression threshold.
- When direct sound was broadband and reflections were filtered, the echo suppression threshold showed an inverse relationship with high-frequency content.
Conclusions:
- The spectral characteristics of both direct and reflected sound significantly modulate echo perception.
- Tailoring spectral content, particularly high frequencies, can effectively manage echo perception and improve acoustic quality in performance venues.
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