Cooling fan control strategy for automotive audio system

摘要

The masking-effect of loud audio passages is utilized to reduce the audibility of the fan noise from a cooling fan (30) in an audio system (10). A power monitor (32) determines an output power of an audio amplifier and generates a power signal proportional to the output power. A switchable cooling fan (30) is positioned to provide a cooling flow of air within the audio system (10) when the cooling fan is turned on. A fan control is coupled to the power monitor and the switchable cooling fan. The fan control compares the power signal with a predetermined threshold and turns on the switchable cooling fan in response to the comparison indicating that reproduction of the amplified audio signals is at an output power level that will substantially mask audible noise created by the switchable cooling fan.