Headphone Equalization via Tone Burst Signal Analysis

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Solution Overview

Problem

Conventional audio headphones struggle to provide personalized and accurate sound reproduction due to variations in user anatomy and brain processing, leading to inconsistent audio experiences across different listeners and headphones, and existing measurement methods are costly, invasive, and do not account for individual perceived frequency responses.

Innovation Solution

A computing system generates user-specific and headphone-specific correction filters using predetermined tone burst reference and test signals during a user-specific audio test, accounting for anatomical and functional differences, and how the brain processes sound, to equalize audio signals and provide consistent sound reproduction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional audio headphones are used without equalization, then the device complexity is low and ease of operation is high, but the measurement precision of individual perceived frequency response is poor and sound quality consistency deteriorates

Engineering Contradiction:
Improveperceived frequency response measurementVSAvoidequalization system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system allows users to perform self-measurement of their individual frequency response using standard headphones and a computer. The user listens to test signals and provides subjective feedback about perceived loudness, which the system uses to generate personalized equalization filters without requiring professional equipment or expertise.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses tone burst test signals as an intermediary to bridge the gap between the headphones and the user's auditory system. These standardized test signals enable objective measurement of subjective perception by comparing the user's response to known reference frequencies.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If user-specific equalization is implemented, then sound quality and consistency are improved, but the time required for audio testing and setup increases

Engineering Contradiction:
Improvesound reproduction consistencyVSAvoidaudio test duration
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system performs equalization setup in advance during an initial audio test, storing the resulting filters for later use. This preliminary measurement eliminates the need for repeated testing, as the personalized equalization parameters are saved and automatically applied to future audio playback.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system efficiently measures frequency response by presenting tone bursts at specific frequencies and measuring the user's perceived loudness differences. By changing only the essential parameters (frequency and perceived loudness) rather than进行全面 characterization, the test duration is reduced while maintaining accuracy.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If professional measurement equipment is used, then measurement precision is improved, but the cost and ease of operation deteriorate due to expensive and invasive procedures

Engineering Contradiction:
Improvefrequency response accuracyVSAvoidmeasurement accessibility
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The system creates a functional copy of professional measurement capabilities using standard consumer equipment. Instead of requiring expensive laboratory instruments, the system uses ordinary headphones and a computer to simulate professional measurement conditions through carefully designed test procedures and signal processing.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The system replaces expensive, delicate measurement equipment with inexpensive, robust alternatives. Standard headphones and software-based signal generation are used instead of costly microphones, couplers, and measurement devices, making accurate frequency response measurement accessible to ordinary consumers.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Data Source

PatentEP2637422B1System for headphone equalization
Publication Date: 2017.05.03 HARMAN INT IND INC
  • EP2637422B1 patent drawingFigure 1
  • EP2637422B1 patent drawingFigure 2
  • EP2637422B1 patent drawingFigure 3

AI summary

A system for headphone equalization includes a stored set of predetermined tone burst reference signals and a stored set of predetermined tone burst test signals that form a range of frequencies used in a user specific audio test to develop a headphone correction filter. A predetermined tone burst reference signal and a predetermined tone burst test signal may intermittently and sequentially drive a transducer included in the headphone. A loudness of the predetermined tone burst reference signal may be fixed and a loudness of the predetermined tone burst test signal may be variable with a gain setting. The gain setting may be used to generate the headphone correction filter.