US Patent 9558732 Active noise control system

An active noise control system includes a first microphone, a controller operably coupled to the first microphone, and a speaker operably coupled to the controller. The first microphone senses a sound input in an audible spectrum, wherein the sound input includes a disturbance noise portion. The controller includes a selection unit and an output unit. The selection unit determines the disturbance noise portion of the sound input based on a highest frequency level of the sound input. The output unit removes the disturbance noise portion from the sound input to generate a filtered sound input. The speaker generates a speaker output based on the filtered sound input.