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A Method to Study Adaptation to Left-Right Reversed Audition
Published on: October 29, 2018
Leaky adaptive filtering approaches for music-driven sound zone generation
Guilhem Pagès1,2, Manuel Melon2, Laurent Simon2
1École Supérieure d'Électronique de l'Ouest, Angers, France.
The Journal of the Acoustical Society of America
|May 22, 2026
Summary
This study introduces new adaptive filtering methods for creating sound zones in dynamic environments. The leaky filtered-x affine projection algorithm (LFx-APA) improves performance for non-stationary audio signals.
Area of Science:
- Acoustics and Signal Processing
- Adaptive Filtering
- Spatial Audio
Background:
- Sound zones create distinct listening areas but struggle in dynamic environments.
- Existing methods fail with music due to temporal correlation and slow convergence.
- Closed-loop algorithms adapt in real-time but are often too slow.
Purpose of the Study:
- To develop adaptive filtering methods for robust sound zone generation in dynamic acoustic conditions.
- To improve convergence speed and performance for non-stationary audio signals.
- To address limitations of existing sound zone technologies in real-world applications.
Main Methods:
- Proposed three leaky gradient descent-based adaptive filtering approaches.
- Introduced the leaky filtered-x affine projection algorithm (LFx-APA).
- Compared LFx-APA against the filtered-x least mean squares (FxLMS) algorithm.
Main Results:
- LFx-APA demonstrated enhanced convergence speed and robustness.
- The algorithm performed well with non-stationary audio signals.
- Simulations in a reverberant room showed improved contrast without increased reproduction error.
Conclusions:
- Leaky gradient descent-based methods, particularly LFx-APA, offer superior sound zone generation in dynamic scenarios.
- LFx-APA is well-suited for non-stationary audio due to its ability to project over multiple past measurements.
- The proposed methods significantly advance the performance of sound zone systems in challenging acoustic environments.
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