NOISE REDUCING DEVICE

PROBLEM TO BE SOLVED: To obtain a noise reducing device which can attain increasing the silencing effect in a human hearing feel and to allows miniaturization. SOLUTION: This noise reducing device, which executes silencing by generating the acoustic waves of the same sound pressure and antiphase and interfering these acoustic waves with the acoustic waves generated from a noise source, has a noise state detecting section 1 which is disposed at a first spot, receives the acoustic waves and transmits the noise state signal formed by filtering the acoustic waves received at the first spot at a frequency characteristic based on the frequency characteristic of the human auditory sensation, a silencing state detecting section 2 which is disposed at a second spot further distant away from the noise source than the first spot, receives the acoustic waves and transmits the silencing state formed by filtering the acoustic waves received at the second spot at the frequency characteristic, based on the frequency characteristic of the human auditory sensation, an arithmetic section 3 which calculates the silencing signal in accordance with the noise state signal and the silencing state signal and a silencing section 4, which is disposed between the first spot and the second spot and generates the acoustic waves of the same sound pressure and antiphase, in accordance with the silencing signal.