Patent ID: 6608906
Filing Date: 2003-08-19
Classification: H04R

Abstract:
An audio system for reproducing audio signals comprising:an amplifier for amplifying said audio signals; a power monitor for determining an output power of said amplifier and generating a power signal proportional to said output power; a switchable cooling fan positioned to provide a cooling flow of air within said audio system when turned on; a fan control coupled to said power monitor and said switchable cooling fan, said fan control comparing said power signal with a predetermined threshold and turning on said switchable cooling fan in response to said comparison indicating that reproduction of said amplified audio signals is at an output power level that will substantially mask audible noise created by said switchable cooling fan; and wherein said fan control performs a plurality of said comparisons of said power signal with said predetermined threshold during a predetermined time window, and wherein said fan control turns on said switchable cooling fan when a count of said comparisons for which said power signal is greater than said predetermined threshold exceeds a predetermined count.