Passive Noise Reduction Any stereo headset or headphone will provide some level of passive noise reduction. In fact, any device that provides a physical barrier to your ear canal will limit your exposure to noise. Industrial noise canceling headphones fit over the ear and are specially constructed to maximize noise filtering. They are packed with layers of high-density foam or other sound-absorbing material, which makes them heavier than other headphones but reduces the background noise by about 15 to 20 dB. This level of noise reduction is essential in workplaces with extreme noise levels, such as airport ground crew areas or factories. Not every work environment requires that level of noise canceling, however. For office workers, a more lightweight, over-the-ear or in-the-ear headset typically provides the required passive noise reduction more comfortably.
Active Noise Canceling (ANC) Beyond passive noise canceling, which involves physically blocking sound, ANC is a technology built into many of our products that further enhance the user experience. This technology uses additional microphones on the back of each speaker that respond well to low-frequency (80 to 700 Hz) background noise. These microphones pick up the background noise, feed it into the ANC circuitry, invert it, then direct it into the same audio path. This happens very quickly, <500 milliseconds, which is not perceptible to the user. The result? The original background noise and the inverted noise cancel each other, leaving just the audio the user wants to hear.