| 摘要 |
PROBLEM TO BE SOLVED: To provide a noise reduction device capable of reducing noise at a control point irrespective of a noise level.SOLUTION: A noise reduction device 300 includes: two speakers 340a, 340b which generate control sounds for canceling noise at a plurality of control points C1, C2 which are noise reduction target positions; two noise controllers 330a, 330b which generate control sound signals for generating the control sounds from the speakers 340a, 340b; and two error microphones 350a, 350b which are arranged at the respective control points C1, C2 to detect error sounds between the noise and the control sounds. The noise controllers 330a, 330b generate the control sound signals based on an error sound detected by the corresponding error microphone among the plurality of error microphones. The noise reduction device 300 further includes an input switching part 395B which causes the respective noise controllers 330a, 330b to input an error sound signal at control points C3 which are newly set based on the plurality of control points C1, C2 and has fewer control points than the plurality of control points C1, C2, when a noise level is larger than a predetermined threshold. |
