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Spatially characterized pseudo-perfect diffuseness via finite-degree spherical harmonic diffuseness.
Tatsuhiro Tanaka1, Makoto Otani1
1Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japantanaka.tatsuhiro@icloud.com, otani@archi.kyoto-u.ac.jp.
JASA Express Letters
|July 3, 2024
Summary
This study characterizes pseudo-perfect sound diffuseness in architectural acoustics. Finite-degree spherical harmonic analysis reveals local spatial diffuseness, introducing the effective radius for characterization.
Area of Science:
- Acoustics
- Architectural Acoustics
- Sound Field Theory
Background:
- Perfectly diffuse sound fields are crucial in architectural acoustics, with established theoretical models.
- Real-world sound fields exhibit partial, not perfect, diffuseness, necessitating theories for pseudo-perfectly diffuse fields.
Purpose of the Study:
- To spatially characterize pseudo-perfect sound diffuseness.
- To investigate finite-degree spherical harmonic diffuseness for directional analysis.
Main Methods:
- Directional characterization of finite-degree spherical harmonic diffuseness.
- Spatial analysis of sound fields in architectural acoustics.
Main Results:
- Finite-degree diffuse sound fields demonstrate local spatial diffuseness.
- The effective radius of diffuseness is proposed as a metric for spatial pseudo-perfect diffuseness.
Conclusions:
- Spatial pseudo-perfect diffuseness can be effectively characterized using the concept of the effective radius.
- This research provides a method for understanding and quantifying non-ideal sound fields in architectural spaces.
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