A noise reducing system comprising: a helmet; two loudspeakers (108, 109) disposed in the helmet at opposing positions; two microphones (110, 111) disposed in the vicinity of the two loudspeakers (108, 109); and an active noise control module having two channels (301, 302) each with an error-signal input, a reference-signal input and an output; wherein: the output of the first channel is electrically coupled to the first loudspeaker and the output of the second channel is electrically coupled to the second loudspeaker; the error-signal input of each channel (301, 302) is electrically coupled to the microphone (110, 111) in the vicinity of the loudspeaker (108, 109) that is electrically coupled to the output of the same channel (301, 302); and the reference-signal input of each channel (301, 302) is electrically coupled to the microphone (111, 110) in the vicinity of the loudspeaker (109, 108) that is coupled to the respective other channel (302, 301); wherein the active noise control module is of a combined feed-forward and feedback type; wherein each channel (301, 302) comprises a feed-forward active noise control filter (304, 307) and a feedback active noise control filter (303, 306); wherein the feed-forward active noise control filter (304, 307) has an input that forms the reference-signal input of the respective other channel; and the feedback active noise control filter (303, 306) has an input that forms the error-signal input of the respective channel. a helmet; two loudspeakers (108, 109) disposed in the helmet at opposing positions; two microphones (110, 111) disposed in the vicinity of the two loudspeakers (108, 109); and an active noise control module having two channels (301, 302) each with an error-signal input, a reference-signal input and an output; wherein: the output of the first channel is electrically coupled to the first loudspeaker and the output of the second channel is electrically coupled to the second loudspeaker; the error-signal input of each channel (301, 302) is electrically coupled to the microphone (110, 111) in the vicinity of the loudspeaker (108, 109) that is electrically coupled to the output of the same channel (301, 302); and the reference-signal input of each channel (301, 302) is electrically coupled to the microphone (111, 110) in the vicinity of the loudspeaker (109, 108) that is coupled to the respective other channel (302, 301); wherein the active noise control module is of a combined feed-forward and feedback type; wherein each channel (301, 302) comprises a feed-forward active noise control filter (304, 307) and a feedback active noise control filter (303, 306); wherein the feed-forward active noise control filter (304, 307) has an input that forms the reference-signal input of the respective other channel; and the feedback active noise control filter (303, 306) has an input that forms the error-signal input of the respective channel. the output of the first channel is electrically coupled to the first loudspeaker and the output of the second channel is electrically coupled to the second loudspeaker; the error-signal input of each channel (301, 302) is electrically coupled to the microphone (110, 111) in the vicinity of the loudspeaker (108, 109) that is electrically coupled to the output of the same channel (301, 302); and the reference-signal input of each channel (301, 302) is electrically coupled to the microphone (111, 110) in the vicinity of the loudspeaker (109, 108) that is coupled to the respective other channel (302, 301); wherein the active noise control module is of a combined feed-forward and feedback type; wherein each channel (301, 302) comprises a feed-forward active noise control filter (304, 307) and a feedback active noise control filter (303, 306); wherein the feed-forward active noise control filter (304, 307) has an input that forms the reference-signal input of the respective other channel; and the feedback active noise control filter (303, 306) has an input that forms the error-signal input of the respective channel.