株式会社ANCラボはアクティブ消音、騒音制御（Active Noise Control）を専門とする会社です。

Low-frequency noise

• There are increasing complaints about low-frequency noises from factories and construction sites these days.
• High-frequency noises can be shut out by acoustic barriers, but low-frequency noises go over them and go into houses with only slight reduction.
• Low-frequency noises come around behind buildings, come through glass windows, reflect at concrete walls, and turn into uncomfortable noises. They may cause mental and physical damage to the neighbors. By just hearing a 60Hz sound for a few minutes, people would lose their appetite.
• When there is a periodic sound noise (sin wave) and once people get conscious of it, the sound is getting more and more annoying. Many countries impose a penalty for such a periodic sound noise.
• Once a low-frequency noise is emitted. it would get really difficult to control and reduce it.
• To settle this problem is to stop emitting, or to cancel the noise by an inverse phase sound near the noise outlet. That is damping the sound by another sound.
• It is effective to use ANC (Active Noise Control) technology to resolve those noise problems.
  Here is some actual site applying ANC.

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High-frequency sound: Reflecting at walls and damping at glass windows.

Low-frequency sound: Coming over walls and passing through glass windows.

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For interested clients

• Contact us for further information. Our experienced staff supports you.
• We measure and analyze the noise at your site, and examine the possibility of ANC effect. 　　
• We check out the efficacy of ANC by using an experiment system.
• We tailor-make an ANC system in a special case.
• We conduct a periodic inspection after the system installation.
• Rental is available.

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