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Optimal source placement for sound zone reproduction with first order reflections.
Marek Olik1, Philip J B Jackson1, Philip Coleman1
1Centre for Vision, Speech and Signal Processing, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
The Journal of the Acoustical Society of America
|December 7, 2014
Summary
Optimizing speaker placement enhances acoustic contrast for personal audio delivery in shared spaces. This study introduces new techniques to improve sound separation, even with reflections.
Area of Science:
- Acoustics
- Signal Processing
- Personal Audio
Background:
- Achieving acoustic separation for personal audio in shared spaces is challenging, especially with reflections.
- Existing active control methods struggle in non-anechoic conditions.
Purpose of the Study:
- To investigate acoustic contrast maximization for personal audio delivery.
- To analyze the impact of geometry on a 2x2 system's performance with reflections.
- To develop and evaluate source positioning strategies for improved acoustic separation.
Main Methods:
- Analytic study of a 2x2 system in a single-reflection scenario.
- Formulation of source position optimization guidelines (Null-Split, Far-Align, Near-Align).
- Numerical optimization to demonstrate techniques on larger systems with up to two reflections.
Main Results:
- Optimized source positions significantly increase acoustic contrast compared to non-optimized arrangements.
- The proposed techniques effectively manage acoustic contrast even with multiple reflections.
- Optimized systems outperform sound power minimization for reflection impact reduction.
Conclusions:
- Acoustic contrast maximization with optimized source positioning is a viable strategy for personal audio delivery.
- The developed guidelines offer practical solutions for improving sound separation in reverberant environments.
- This research provides a foundation for designing more effective personal audio systems.
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