Multi-Listening Audio Tuning Using Similarity-Based Response Alignment

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Solution Overview

Problem

Achieving a balanced frequency response, particularly a balanced bass response, across multiple listening positions in multi-channel audio systems is challenging due to varying acoustic interactions and complex tuning parameters, making manual and conventional automated solutions impractical.

Innovation Solution

An automated method using a similarity metric-based optimization process to determine audio signal processing parameters, including channel delays and allpass filters, to align and enhance the frequency responses across all listening positions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If manual tuning of audio signal processing parameters is performed to optimize frequency response at one listening position, then the frequency response at that position is improved, but the frequency response at other listening positions deteriorates

Engineering Contradiction:
Improvefrequency response optimizationVSAvoidfrequency response consistency across listening positions
Core Design Contradiction:
Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The patent divides the audio system into multiple independent speaker channels (e.g., four woofers) and measures the audio response at multiple listening positions separately. By segmenting the system into individual speaker contributions at each position, the method enables independent analysis and optimization of each channel's effect on frequency response across different locations.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent systematically adjusts audio signal processing parameters (delays, gains, equalization filters) for each speaker channel based on measured audio responses. By changing these parameters iteratively and evaluating the impact on frequency response at multiple listening positions, the method optimizes overall system performance rather than focusing on a single position.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If the number of audio signal processing parameters is increased to achieve better frequency response balance, then the optimization capability is improved, but the system complexity increases

Engineering Contradiction:
Improvefrequency response balanceVSAvoidnumber of tuning parameters
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent implements a feedback-based optimization process where audio responses are measured at multiple listening positions, compared against target frequency responses, and used to automatically adjust signal processing parameters. This closed-loop feedback system reduces the need for manual tuning of numerous parameters by using measurement data to guide automatic optimization.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs self-optimization by automatically measuring audio responses, calculating parameter adjustments, and applying corrections without requiring extensive manual intervention. The automated optimization process handles the complexity of multiple parameters by using algorithms to determine optimal settings based on measured performance.

Inventive Principle:
Principle #25Self-service

3Reliability

If conventional automated solutions adjust delays and gains to maximize constructive interference, then the audio response at specific positions is improved, but the ability to optimize complex audio systems with multiple speakers and varying listening positions is limited

Engineering Contradiction:
Improveaudio response optimizationVSAvoidoptimization capability for complex systems
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent measures and analyzes the audio contribution of each individual speaker channel at each listening position separately. By segmenting the overall system response into individual speaker contributions, the method can optimize each channel's delay, gain, and equalization independently while considering its impact on all listening positions.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent extends conventional optimization by adjusting multiple parameter types (delays, gains, equalization filters) for each speaker channel based on measured audio responses at multiple positions. This comprehensive parameter adjustment capability enables optimization of complex systems with many speakers and varying listening positions beyond what conventional single-parameter adjustments achieve.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4672785A1Similarity metric-based multi-listening position audio system optimization
Publication Date: 2025.12.31 HARMAN BECKER AUTOMOTIVE SYST GMBH
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AI summary

A computer-implemented method for determining audio signal processing parameters for a multichannel audio system including a plurality of speakers is disclosed. The method involves obtaining at least one first audio response at a first listening position and at least one second audio response at a second listening position, where each audio response corresponds to a respective channel audio signal output by a respective speaker over a predetermined frequency range. The audio signal processing parameters are determined based on a similarity metric calculated between the first and second audio responses over at least a part of the predetermined frequency range. The determined audio signal processing parameters are then provided for further processing of at least one of the channel audio signals, enabling optimization of the audio system's performance across multiple listening positions.