A device and method for testing the acoustic performance of products

Abstract

The invention discloses a device and method for testing the acoustic performance of a product. The device is provided with a closed pressure field acoustic cavity structure on a bearing mechanism, and adopts a structure in which a sound source speaker is placed outside and a reference microphone is close to the sound outlet of the cavity. And during the testing process, through the calibration of the sound source and the post-processing steps of the collected signal, the problem of the inconsistency of the sound pressure performance received by the product is solved, and the interference of the sound source itself is reduced, especially when it is in the low frequency band, the required sound pressure can also be easily achieved. The pressure level can eliminate the error in the test process and stabilize the test results.

Description

technical field [0001] The invention relates to the technical field of acoustic testing, in particular to a device and method for testing the acoustic performance of products. Background technique [0002] With the mass production of electronic products and the continuous pursuit of sound quality by consumers, the requirements for the acoustic performance and consistency of electronic products are getting higher and higher. Testing the consistency of acoustic performance of products has become a key point. The test environment for the consistency of acoustic performance The requirements are very strict, not only require a very high signal-to-noise ratio, but also have very high requirements for the sealing of the test environment. At the same time, the test sound source needs to be tested within a certain sound pressure level range to ensure the stability and authenticity of product performance. This requires the test environment to have extremely high sound insulation perfo...

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Problems solved by technology

[0003] The structure of the test device used in the prior art generally adopts that in a confined space, a sound source is placed as close as possible to the sound receiving hole of the product to be tested, and a reference microphone is placed inside the space to collect comparison signals. Although the interference of external noise is reduced, it cannot be completely eliminated, and the actual signal collected by the product is not completely consistent with the actual signal collected by the reference microphone, so the comparison error between the two will increase; the test methods in the prior art generally include: The device assembly step, the state-to-be-tested step, the product testing step and the data comparison step, the signal collected by this method has a large error, and it is difficult to meet the specific sound pressure level in the low frequency band, so the acoustic test result of the product is poor

[0004] like figure 1 As shown, an existing patent document with a publication number of CN105722003A discloses a MEMS microphone testing mechanism, which includes a cavity, a sound source speaker located in the cavity, a reference microphone, a product placement groove and a pressing structure, and the bottom of the groove is provided with There is a sound inlet. This mechanism can conduct acoustic tests on the forward sound or the rear sound microphone. However, on the one hand, because the sound source speaker is built in the cavity, the sound cavity is large and the performance of the entire sound emitting surface of the speaker is inconsistent, resulting in different products. The sound pressure performance is different, the sound source speaker and the cavity are not sealed and isolated, the sound cavity will be affected by the vibration of the sound source speaker itself during the test, and the collected signal will be disturbed by vibration, and the distance between the reference microphone in the mechanism and the sound outlet of the cavity is relatively small. Therefore, there is a difference between the acquisition signal of the reference microphone and the acquisition signal of the product sound inlet, and the error of the measured result is relatively large. On the other hand, the test method of this patent is consistent with the general test method of the prior art, so it cannot meet the specific sound The signal requirements of the pressure level, due to the signal error and other losses in the test process, the error of the final test result is relatively large, especially in the low frequency band, it is very difficult to meet certain specific sound pressure levels, even if the required sound pressure level is reached , it will also cause the sound source to burn out or the signal to be seriously distorted

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