Ambient noise is one of the banes of modern life — the byproduct of a technologically advanced world, where the whir of computer hard drives, the hum of air conditioners, and the beeps and blips of computers and smart devices combine into a cacophony of background music.
Some people actually like white noise, as it is sometimes called, and have a hard time functioning when it’s too quiet, while the buzz of gadgets drives others crazy. Either way, however, scientists have found that ongoing background noise is clearly linked to increased stress levels, and can induce the release of a body chemical called cortisol – too much of which can negatively affect brain functions such as planning, reasoning, impulse control, and even short-term memory. According to former US Surgeon General William H. Stewart, “calling noise a nuisance is like calling smog an inconvenience. Noise must be considered a hazard to the health of people everywhere.”
One Israeli company has made it its mission to lower the levels of background noise in our daily lives. Rehovot-based Silentium has a computer algorithm-based silencing technology that can be applied to a wide variety of business and consumer products.
Silentium’s system, called Active Noise Control (ANC), is based on producing an “anti-noise” signal that destructively interferes with the original sound wave and cancels out the noise. The system, an advanced form of noise cancellation technology, is placed within the body of a device. It comprises a sensor microphone that picks up the sound and measures its frequency and amplitude, and a microchip that absorbs the noise input emitted by the noise source and transforms it into output in an inverted phase, thus canceling it. The ANC can be integrated with an existing product, cutting off the noise at its source and allowing products to operate up to 90 percent more quietly, according to the company.
Among the company’s most recent innovations is an add-on for kitchen stove hoods that reduces noise significantly. The hoods vacuum out odors, smoke, and other unwanted by-products of cooking, and are used in settings from home kitchens to restaurants, hotels, and large commercial food manufacturer facilities. But the noise level from hoods is sometimes akin to a real vacuum cleaner, and homemakers, and especially workers, who are subject to them often find themselves with a headache at the end of the day.
In a partnership with Italy’s Faber, one of the largest manufacturers of kitchen hoods in the world, Silentium has developed what officials of both companies believe is the quietest hood in the word. Silentium’s ANC technology, built into the hood, reduces the noise level of hoods by 13 decibels and lowers the frequency of the emitted sound, so listeners perceive it as even quieter. The result, said Silentium CEO Yossi Barath, is a hood that makes the sound of rustling paper, instead of the din of exhaust noise that other hoods make.
Silentium produces solutions for some other modern noisemakers, including heating/air conditioning (HVAC) systems, and computer servers, for use in server farms, where the noise made by spinning disks, combined with the racket made by the fans and air conditioners needed to keep them cool, produce a mighty din. The company’s basic sound-repression system — called the S-Cube kit, which allows manufacturers to easily integrate Silentium’s noise cancellation technology into their products — has been deployed in a wide variety of settings, including telecommunications companies like Huawei and Nokia, IT product makers like Ciara Technologies, and educational institutions like the Polytechnic University of Madrid.
The company even gets fan mail, in the form of testimonials, but Silentium isn’t surprised. “Fatigue, stress, and hearing impairment are but a few of the symptoms people suffer from excessive noise, significantly affecting quality of life,”said Barath. “Silentium’s ‘Silence in a Chip’ disruptive technology instantly gives manufacturers the ability to design products with a significant competitive edge.”