Abstract: This paper proposes a method of using neural network to judge whether a loudspeaker is good or not. First, the method of how to obtain the Rub & Buzz curve and the BP model including its training methods are simply introduced. Besides, the comparison between the basic BP algorithm and the conjugate gradient algorithm is also made. Then the Rub & Buzz curve is used as the BP network's input vector and the judgment result of experienced worker is used as the BP network's output vector and use the conjugate gradient algorithm to train the network. Finally, the trained BP network can judge whether the measured loudspeaker is good or not. The experimental results show that judging a loudspeaker is good or not by a threshold, which is set up by engineer, can be replaced by artificial neural network, and the false alarm rate is greatly reduced.