Seat-Integrated Sound System for Wider Audio in Small Cabins

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In limited spaces, early reflections from room boundaries corrupt the perceived three-dimensional sound image, making it difficult for users to correctly position recorded voices and instruments, as the direct signal from speakers is masked, leading to a decreased sound quality when sound signals are output by multiple transducers.

Innovation Solution

A sound system with a processing unit that controls electrical delay, frequency characteristics, and signal levels for transducers positioned below the ear, specifically on a vehicle seat's backrest, to minimize the influence of the environment and restore masked signal components, allowing users to perceive a wider audio signal without localizing the sound source.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If transducers are positioned in a limited space such as a vehicle cabin, then the sound system can be compact and suitable for small environments, but early reflections from room boundaries mask the direct signal and corrupt the three-dimensional sound image

Engineering Contradiction:

Improvesound system sizeVSAvoidearly reflections masking direct signal

Core Design Contradiction:

Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

The patent positions transducers in the vertical dimension (above and below the seat) rather than only in the horizontal plane. This dimensional change allows sound to be delivered from directions that are less affected by early reflections from side boundaries, thereby maintaining sound image quality in compact spaces.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent applies different signal processing treatments to different transducers based on their specific positions. Transducers above the seat receive different electrical delay, frequency characteristic, and signal level adjustments compared to transducers below the seat, optimizing each transducer's contribution to the overall sound image while compensating for position-specific reflection patterns.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If sound signals are output by multiple transducers in a limited space, then the sound system can provide omnidirectional coverage, but users can localize the sound from specific transducers which loses the impression of a wide audio signal

Engineering Contradiction:

Improvesound coverageVSAvoidwidth of audio signal

Core Design Contradiction:

Adaptability or versatilityVSLoss of information

Solution Approach 1:

The patent systematically varies multiple parameters (electrical delay, frequency characteristics, signal level) for signals sent to different transducers. These parameter changes create subtle differences in sound arrival that prevent easy localization while maintaining omnidirectional coverage, preserving the impression of a wide audio signal.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent dynamically adjusts signal parameters in real-time based on the user's position and the specific transducer being activated. This dynamic adaptation ensures that sound coverage remains omnidirectional while the processed signals maintain the perceptual width of the audio signal by preventing discrete localization.

Inventive Principle:

Principle #15Dynamics

3Object-affected harmful factors

If transducers are positioned above or below the user's ears, then sound signals can be delivered from directions less affected by side reflections, but the user has difficulty localizing the sound source which may reduce perceived sound quality

Engineering Contradiction:

Improveside reflections influenceVSAvoidsound localization accuracy

Core Design Contradiction:

Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent converts the potential disadvantage of poor localization (when sound comes from above or below) into a benefit by using it to mask the presence of individual transducers. The processed signals from these transducers restore masked signal components and maintain the width of the audio signal, turning localization difficulty into an advantage for preserving sound image quality.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 system effectively restores the masked signal components, maintaining the intended width of the sound signal and enhancing the perceived sound quality by positioning transducers below the ear, where sound localization is less accurate, thus overcoming the limitations of early reflections in small spaces.

Implementation Method 1

a plurality of transducers configured to output the sound signals

Methodology Applied

Scientific EffectElectroacoustic transduction:

Implementation Method 2

The processing unit is configured to individually control at least an electrical delay, a frequency characteristic and a signal level with which the sound signals transmitted to the plurality of transducers are output by each of the plurality of transducers

Methodology Applied

Scientific EffectElectrical delay control:

Implementation Method 3

Methodology Applied

Scientific EffectFrequency characteristic control:

Implementation Method 4

Methodology Applied

Scientific EffectSignal level control:

Implementation Method 5

When reproducing audio signals in a limited space, reflection from boundaries will influence the perceived staging of the reproduced audio signals

Methodology Applied

Scientific EffectAcoustic reflection: Reflection

Data Source

PatentEP3906707B1Sound system with improved width of the perceived sound signal

Publication Date: 2024.02.28 HARMAN BECKER AUTOMOTIVE SYST GMBH

Figure 1
Figure 2
Figure 3

AI summary

The invention relates to a sound system (100) configured to output sound signals to a user located in a defined environment (20), comprising a plurality of transducers (111 - 114, 121 - 124) configured to output the sound signals, a processing unit (130) configured to individually control at least an electrical delay, a frequency characteristic and a sound level with which the sound signals transmitted to the plurality of transducers are output by each of the plurality of transducers, and a seat (200) for a user (50) to which the sound signals are output, the seat comprising a seating surface (230) and a backrest (210) configured support a back of the user sitting on the seating surface (230), wherein the backrest (210) comprises an upper surface (211) defining an upper end surface of the backrest (210) in a position when the user is sitting on the seat, wherein the defined environment influences the sound signals as perceived by the user sitting on the seat. The plurality of transducers comprise at least one first transducer (121-124) attached to the seat (200) in such a way, that the at least one first transducer (121-124) is positioned below the upper surface, wherein the processing unit is configured to control at least one of the delay, frequency characteristic and sound level of the sound signal output by the at least one first transducer so as to at least partially remove the influence of the defined environment on the sound signal as perceived by the user.