Vented Speaker Module With Passive Radiator for Low-Frequency Extension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing speakers face challenges in improving low-frequency extension capability and sound pressure level due to acoustic short circuits and the need for larger sound boxes that occupy excessive space.
Innovation Solution
A speaker module with a frame body, speaker, and passive vibration plate, where the passive vibration plate's resonant frequency is higher than the speaker's, and a vent communicates with a large rear cavity, allowing sound waves from both to be superposed, enhancing sound pressure level and low-frequency extension without increasing the module's volume.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the rear cavity volume is increased to improve low-frequency extension capability, then the low-frequency performance is enhanced, but the device occupies excessive space
Solution Approach 1:
The patent combines the functions of the rear cavity and passive vibration plate into a integrated structure. The passive vibration plate is positioned within the rear cavity space, allowing the same volume to serve both as the acoustic chamber and as the mounting structure for the passive radiator, thereby improving low-frequency extension without increasing overall device volume.
Solution Approach 2:
The patent utilizes the third dimension by stacking the passive vibration plate vertically within the rear cavity space. This dimensional arrangement allows the passive vibration plate to be accommodated within the existing cavity volume rather than requiring additional horizontal space, effectively improving low-frequency response without expanding the speaker module's footprint.
2Power
If the sound pressure level is increased by adding more acoustic components, then the sound pressure level is improved, but the device complexity increases
Solution Approach 1:
The passive vibration plate serves a dual function: it acts as both a structural component defining the rear cavity volume and as an active acoustic element that radiates sound. This self-service approach allows the same component to contribute to both the acoustic chamber geometry and the sound pressure generation, thereby improving SPL without proportionally increasing device complexity.
Solution Approach 2:
The passive vibration plate is designed to perform multiple functions simultaneously: it serves as the boundary defining the rear cavity, acts as a passive radiator driven by acoustic pressure, and contributes to the overall structural integrity of the speaker assembly. This multi-functionality reduces the need for separate dedicated components, thereby improving sound pressure level while limiting complexity growth.
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 solution improves low-frequency extension and sound pressure level by superposing sound waves from the speaker and passive vibration plate, reducing the need for a larger volume and minimizing space occupation.
Implementation Method 1
a sound is generated through vibration based on fluid-solid coupling
Implementation Method 2
sound waves radiated outward by the speaker and the passive vibration plate through vibration can be superposed
Implementation Method 3
a resonant frequency of the passive vibration plate is greater than a resonant frequency of the speaker
Data Source
AI summary
A speaker module includes a frame body, a speaker, and a passive vibration plate. A resonant frequency of the passive vibration plate is greater than a resonant frequency of the speaker. Both the speaker and the passive vibration plate are installed on the frame body, and a cavity is formed among the frame body, the speaker, and the passive vibration plate. The frame body is provided with a vent, and the vent communicates with the cavity.