认为主动噪声控制是解决低频噪声问题的有效方法。国家在将该技术应用于工业风机和商用空气处理器的进气和排气管道时，采用了无限脉冲响应自适应滤波器方法。基本概念是创建一个振幅和频率与噪声声场相同但相位相反的声场。这个相反的场抵消了噪声场。与传统消声器相比，它的突出优点是超低噪音- 频率衰减，流量限制可忽略不计。注意到与传统消音器相比，该系统的其他优点，并解释了它们的操作。关键词:噪音控制，隔音，风扇，建筑。引用:研讨会，ASHRAE Trans。，1993年，第99卷，第2部分，论文编号DE-93-1-1429-439，图7，表2，参考文献。

Maintains that active noise control is a proven solution to low-frequency noise problems. States an infinite impulse response adaptive filter approach has been used in the application of this technology to the intake and discharge ducts of industrial fans and commercial air handlers. The basic concept is to create an acoustic field equal in amplitude and frequency to the noise acoustic field but opposite in phase. This opposing field cancels the noise field. The outstanding advantage over conventional silencers is superior low-frequency attenuation with negligible flow restriction. Notes additional benefits of the system compared to conventional silencers and explains their operation.KEYWORDS: Noise control, antisound, fans, buildings.