Asymmetrical Loudspeaker Waveguide for Automotive Audio Directivity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing loudspeaker assemblies in automotive applications lack effective directivity control and efficiency, particularly in shaping sound fields to focus audio towards vehicle occupants while minimizing sound transmission to unnecessary areas.

Innovation Solution

A loudspeaker assembly with an asymmetrical waveguide that includes a creased flare and continuous blend, allowing for customizable trim shapes without affecting performance, and incorporates a grille to enhance off-axis audio performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a waveguide is used to shape sound field and control directivity, then audio transmission towards vehicle occupants is improved, but sound dispersion to unnecessary areas cannot be minimized

Engineering Contradiction:
Improvedirectivity controlVSAvoidunwanted sound dispersion
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The waveguide employs an asymmetrical geometry design where the front surface differs from the rear surface, allowing independent optimization of sound projection towards occupants while controlling dispersion to unnecessary areas. The asymmetrical shape enables different acoustic functions at different locations of the waveguide structure.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The waveguide incorporates locally varied surface characteristics including creased flare regions and continuous blend regions. These local variations in surface geometry create specific acoustic zones that control sound behavior in different directions, enabling focused audio transmission while minimizing unwanted dispersion in specific areas.

Inventive Principle:
Principle #3Local quality

2Adaptability or versatility

If waveguide geometry is customized for specific trim shapes, then integration with vehicle interior is improved, but manufacturing complexity increases

Engineering Contradiction:
Improvetrim shape customizationVSAvoidwaveguide geometry complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The waveguide is designed as a separable component that can be independently manufactured and then integrated with different vehicle trim pieces. This segmentation allows the waveguide to maintain a standardized acoustic structure while adapting to various trim shapes through separate mounting, reducing manufacturing complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The waveguide employs a universal mounting interface and standardized acoustic structure that can be integrated with multiple different trim shapes. This multi-functional design allows the same waveguide component to serve various vehicle interior configurations without requiring custom manufacturing for each trim variation.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Productivity

If waveguide focuses sound towards occupants, then audio efficiency is improved, but sound transmission to necessary areas may be reduced

Engineering Contradiction:
Improveaudio transmission efficiencyVSAvoidsound energy distribution
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The waveguide creates dynamic sound distribution patterns that adapt to the acoustic environment. The creased flare and continuous blend geometries produce varying degrees of sound focus and dispersion at different frequencies and angles, optimizing both efficiency and coverage across the audible spectrum.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The waveguide utilizes changes in surface geometry parameters including flare angles, curvature radii, and surface area distributions to control sound propagation. By carefully adjusting these geometric parameters, the waveguide achieves optimal balance between focused transmission for efficiency and adequate dispersion for coverage.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The waveguide and grille combination improves audio directivity and efficiency, ensuring focused sound transmission to vehicle occupants and reducing unwanted sound dispersion, while maintaining consistent frequency response across different seating positions.

Implementation Method 1

The waveguide being configured to control a directivity of the audio output

Methodology Applied
Scientific EffectAcoustic waveguide: Waveguide

Implementation Method 2

the waveguide may be used to either narrow or widen the sound field of audio transmitted from the loudspeaker

Methodology Applied
Scientific EffectAcoustic focusing: Focusing

Data Source

PatentEP4207800B1Loudspeaker assembly with a waveguide
Publication Date: 2025.11.12 HARMAN INT IND INC
  • EP4207800B1 patent drawingFigure 1
  • EP4207800B1 patent drawingFigure 2~3
  • EP4207800B1 patent drawingFigure 4~5

AI summary

In at least one embodiment, a loudspeaker assembly is provided. The loudspeaker assembly includes a loudspeaker and a waveguide. The loudspeaker includes a diaphragm to transmit an audio output. The waveguide being asymmetrical and at least partially surrounding the diaphragm. The waveguide being configured to control a directivity of the audio output.