USB Audio Volume Equalization to Prevent Sudden Loud Sound

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

When an audio device connects to a host apparatus via USB, sudden loud sounds can occur due to volume value discrepancies, as existing systems change the host's volume value to the maximum, disregarding the audio device's pre-set volume settings.

Innovation Solution

The audio device performs volume equalization by comparing the host's volume value with its own and adjusts the volume step values to match, ensuring the audio device maintains its pre-set volume while synchronizing with the host's settings, preventing sudden loud emissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the audio device receives and sets the volume value from the host apparatus, then volume equalization between host and audio device is achieved, but sudden loud sound may be emitted immediately after connection which can damage the device or adversely affect human body

Engineering Contradiction:
Improvevolume equalizationVSAvoidsudden loud sound
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies preliminary action by detecting the host's volume value in advance before setting it in the audio device. The system retrieves the volume value from the host apparatus, compares it with the currently set volume value, and only then proceeds to update if necessary. This preliminary detection and comparison prevents sudden loud sounds by ensuring the volume adjustment is controlled and intentional, not abrupt and harmful.

Inventive Principle:
Principle #10Preliminary action

2Object-affected harmful factors

If the volume value received from the host is disregarded to prevent sudden loud sound, then device safety is maintained, but equalization to the volume setting value of the host is not made

Engineering Contradiction:
Improvedevice safetyVSAvoidvolume equalization
Core Design Contradiction:
Object-affected harmful factorsVSAdaptability or versatility

Solution Approach 1:

The patent implements feedback by continuously monitoring and comparing the host's volume value with the audio device's current volume value. The system retrieves the host's volume setting, compares it with the locally stored value, and decides whether to update based on this feedback loop. This feedback mechanism ensures that volume equalization occurs only when appropriate, maintaining both device safety and proper volume synchronization with the host.

Inventive Principle:
Principle #23Feedback

3Ease of operation

If the volume value is changed to the maximum value when connected to host apparatus, then normal sound volume control by application is enabled, but the volume value of the host system is changed by host-side program rather than audio device

Engineering Contradiction:
Improvesound volume controlVSAvoidcontrol authority
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent applies inversion by reversing the traditional approach where the host controls the audio device's volume. Instead, the audio device actively retrieves the host's volume value and decides whether to adopt it, thereby maintaining control authority. The audio device initiates the volume value acquisition from the host, compares it with its current setting, and makes the final decision on whether to update, thus inverting the control flow while enabling proper volume control.

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentEP3133488B1Audio device, audio system, and volume value control method
Publication Date: 2021.09.01 YAMAHA CORP
  • EP3133488B1 patent drawingFigure 1
  • EP3133488B1 patent drawingFigure 2
  • EP3133488B1 patent drawingFigure 3

AI summary

An audio device (1) is provided with: an amplifier including a volume control unit (120); a communication unit communicating with a host device (2); and a control unit (11) that sets a volume value to the volume control unit (120). The control unit (11) receives, from the host device (2) via the communication unit, an instruction value that instructs the volume value to be set to the volume control unit (120), compares the instruction value and a set value with each other, said set value being the volume value set to the volume control unit (120), and transmits, to the host device (2) via the communication unit, instruction signals based on the comparison results.