Abstract: A combine usage of both measuring the low order harmonic distortion and the sum of high order harmonic distortion in the loudspeaker acoustics response for defect detection is presented in this paper.Based on the analysis of the time domain and frequency domain characteristics of the defect loudspeaker samples and learning from the ability of human hearing,an external principle of the defect measurement is firstly proposed.Secondly,according to modeling the nonlinear system in Volterra series,stimulating the continue logarithmic sweep signal,deducing the response of the test system under these conditions,a fast algorithm is proposed to realize the high-pass and band-pass tracking filter the acoustic signal,and fulfill the detecting of the loudspeaker defects.Not only the validity and feasibility of this method,but also the efficiency was proved by the results of both lab experiment and several factory tests.