Research on audio quality test methods for smart video doorbell products

3.3.1 THD test

Test steps:

(1) Calibrate the artificial ear using a standard artificial mouth;

(2) Use an audio analyzer to generate a simulated test audio signal with a frequency of 1 kHz and an amplitude of 200 mV;

(3) Use an audio analyzer to analyze the audio signal collected by the artificial ear, observe and record the THD index of the product (the analysis can be combined with the audio spectrum and time domain waveform);

(4) Repeat the above steps several times to avoid test contingencies.

3.3.2 Spectrum Analysis

Test steps:

(1) Use a standard artificial mouth to calibrate the artificial ear (if it has been calibrated in the previous test, it does not need to be calibrated again in this test);

(2) Use an audio analyzer to generate a simulated test audio signal with a frequency of 1 kHz and an amplitude of 200 mV;

(3) Use an audio analyzer to analyze the audio signal collected by the artificial ear, save and observe the analyzed audio spectrum;

(4) Repeat the above steps several times to avoid test contingencies.

3.3.3 Rub & Buzz test
Test steps:

(1) Use a standard artificial mouth to calibrate the artificial ear (if it has been calibrated in the previous test, it does not need to be calibrated again in this test);

(2) Use an audio analyzer to generate a simulated test audio signal with a frequency of 1 kHz and an amplitude of 200 mV;

(3) Use an audio analyzer to analyze the audio signals collected by the artificial ear, and observe and record the product's rub and buzz indicators;

(4) Repeat the above steps several times to avoid test contingencies.

3.3.4 Frequency response test

Test steps:

(1) Use a standard artificial mouth to calibrate the artificial ear (if it has been calibrated in the previous test, it does not need to be calibrated again in this test);

(2) Use an audio analyzer to generate a frequency sweep test audio (frequency range 20Hz-20kHz, linear sweep, 30 sweep points, amplitude 200mV);

(3) Use an audio analyzer to analyze the audio signals collected by the artificial ear, and observe and record the product frequency response indicators;

(4) Repeat the above steps several times to avoid test contingencies.

IV. Conclusion

Based on this test solution, an observable and repeatable quality assessment can be performed on the audio transmission processing link of smart video doorbell products. Whether it is for R&D or production, it can provide quantitative and visual parameter comparison. If product quality problems are encountered again, the fault can be located well and feedback can be quickly given to the R&D department to optimize the corresponding product modules.

The core test equipment of the entire test is the A5 audio analyzer, which has a very user-friendly operation interface and provides reliable test accuracy, which is now a consensus in the industry.