A New Nonstationary Test Procedure For Improved Loudspeaker Fault Detection

Loudspeaker fault detection is a difficult industrial problem for both manufacturing fault detection and maintenance. A new brief (<100-ms), nonstationary test signal aimed at detecting acoustic loudspeaker faults is presented. This signal is composed of four simultaneous chirp components and contains all the frequencies in the loudspeaker frequency range. The signal processing technique used to process the recorded loudspeaker responses is based on optimized time-frequency representations (TFRs). The TFR corresponding to a given loudspeaker is compared to a reference TFR using a time-frequency distance measure. The efficiency of the proposed test procedure, as well as its practical interest, are shown with real data.