A Novel Technique for Detecting and Locating Loudspeaker Defects

A novel technique for the measurement of rub & buzz using a fast tracking high pass filter is presented first in this paper. In the tests of 100,000 loudspeaker samples on production line, the very low missed detection was 0.006% and the false alarm rate was 4.68% with this method compared with human hearing tests. Then a method consists of detecting loudspeaker defect and estimating loudspeaker displacement without using a laser displacement sensor is launched. Only the current response of loudspeaker is used to predict loudspeaker displacement. And there is less than 3% error in phase component according to the direct laser measurement. Several experiments proved this method was very effective.