Over the past half-century, technology has improved virtually every aspect of human life. However during this period, not much has changed in the world of industrial hearing protection. Workers basically can choose either earplugs that are inserted into the ear or earmuffs that cover the ears. These are called passive ear defenders because they employ acoustic foam to block noise waves from entering the ear. This is a very effective way to protect users from high- frequency noise, however low-frequency noise generated by engines, motors and fans is more challenging. Low-frequency noise waves are longer, can carry great distances and can penetrate passive barriers, even cement walls. Now there's a new innovation in hearing protection that employs active noise reduction. The NoiseBuster® Active Noise Reduction (ANR) Earmuff provides more complete protection from a wider range of noise frequencies, particularly low-frequency noise generated by engines, motors and fans that is prevalent in many industrial settings. The passive component of the NoiseBuster ANR Earmuff has a very competitive Noise Reduction Rating (NRR) of 26dB and the ANR component provides as much as 20dB of added noise reduction within the low-frequency bandwidth of 20-800 Hz. The earmuff is priced at $149. The NoiseBuster ANR system uses a microphone inside the ear cup to listen to noise coming into the ear. Using electronics, the system takes that information and uses it to create a noise wave that is identical to, but directly opposite of, the one coming into the ear. The "anti- noise" wave is output through a speaker, also located in the ear cup. When the two waves (the noise wave and the anti-noise wave) meet, the noise is significantly reduced. ANR is the only effective method of attenuating low-frequency noise. Prolonged exposure to noise, including low frequency noise, is known to cause many detrimental psychological and physiological effects including: fatigue, anxiety and depression; loss of concentration and productivity; and headaches, high blood pressure and hearing loss. Low frequency noise interferes with communication because it masks consonant sounds--the sounds that make speech intelligible. In environments where there is an abundance of low frequency noise people express the ability to hear another speaking, but not to understand what is being said. Low frequency noise from engines, motors and fans dominates in many industrial settings. Some of the loudest include: airfields, forestry, payloaders, diesel locomotives, forges, factories, highways, ship engine rooms and heavy tractors. Communication in these environments is often crucial and therefore low frequency noise reduction is a necessity. ANR technology is not a new idea. The concept of creating a copy of a sound and using that copy to cancel the original sound dates back to the early 1900's. These first ANR systems used a simple "delay and invert" approach which was limited in its effectiveness. In the mid- 1970's, rapid advancement of ANR systems was achieved with the use of adaptive filters to generate the anti-noise. This allowed the systems to adapt continuously to changes in their external world and in their own components. A second breakthrough in the mid-seventies was the recognition that many noises, particularly those produced by man-made machines, are periodic or tonal. This tonal noise allowed for a more effective ANR solution since each repetition created a predictable harmonic pattern, which enabled the active system to generate a more accurate anti-noise signal. Widespread application, however, still had to wait due to cost and size constraints. The electronic technology available in the 1970's was not sufficient for implementing active noise control systems in a cost effective manner. Today, technology has evolved to the point where cost-effective electronics can perform the complex calculations involved in noise cancellation. ANR can now be applied to difficult environmental noise problems at a reasonable cost. Hearing protection is not only important for industrial workers, but for anyone who is exposed to noise on a regular basis. The NoiseBuster's audio input feature makes it an excellent choice for do-it-yourself users of lawnmowers and power tools who want to listen to music, as well as for motor sports fans when used in conjunction with scanners (devices that allow fans to hear the radio communications of race car drivers and pit crews). For audio to be heard in the presence of noise it must be overamplified above the noise, thereby creating a possible hearing hazard. The NoiseBuster ANR Earmuff cancels background noise so that music can be enjoyed at safer volume levels. The product delivers excellent audio quality, comparable to that of higher-priced, noise canceling audio headphones currently on the market. "We believe the NoiseBuster ANR Earmuff is a true breakthrough in industrial hearing protection," said Richard Hennessey, President, Pro Tech. "Passive earplugs and earmuffs are effective against mid- and high- frequency noise, but they lose their effectiveness at 500 hertz and below. Electronic low frequency noise cancellation delivers an additional level of protection and enables workers to hear crucial sounds such as speech and warning signals." Mr. Hennessey continued, "Additionally, at this price point, many consumers can benefit from using the product while engaged in high-noise activities such as mowing the lawn. The NoiseBuster is an affordable and enjoyable solution because users can listen to music without overamplification or distortion. And motor sports fans won't miss one minute of the action on the scanner but can listen safely." The NoiseBuster ANR Earmuff is powered with a single AA battery that provides 65 hours of use. The unit is resistant to water, moisture, contaminants, mechanical shock and vibration. The product features soft, pliable ear cushions and an adjustable headband. The unit is warrantied for six months. 217 Westport Road, Wilton, CT 06897 ph. 203-210-7230, fx. 203-210-7229, www.noisebuster.net