Pop Noise in Automotive Audio Systems - Causes and Cures

The audible “pop” sounding noise heard at the loudspeaker when a radio and/or amplifier module is switched on/off has become generically known as “pop-noise”. This phenomenon has become a particularly sensitive issue in recent years especially to the “Big Three” in their drive to acquire true high fidelity sounding systems in the demanding automotive environment. The causes and cures are very well understood by power audio I.C. designers and producers and involve a close integration between optimization of IC design and final system implementation. This paper serves to explain these causes and what has been done to reach a satisfactory and acceptable cure.