When air molecules collide they make a noise of -23db. The Brownian Motion, as this is called and the lowest noise known to man discounting the vacuum of space, is just negative 3 decibels more silent than the most quiet place on earth.
Building 87 holds Microsoft's remarkable anechoic chamber and has au courant acoustic environment that registers at -20.6db. Its walls are fitted with anechoic wedges for sound absorption and is sealed by a very thick door. The chamber has sound absorption levels of 99-100% and is perfect for testing audio equipments. It was built in a little over a year under the collaboration of Microsoft with Eckel Noise Control Technologies.
Microsoft dubbed Building 87 to be 'where sound goes to die.' An extended stay in the chamber would effectively weaken a person's sense of balance because the surrounding silence takes away the auditory cues of a regular environment.
Microsoft Principal Human Factors Engineer Hundraj Gopal says, "We designed this and other super-quiet acoustically-controlled chambers to engineer and build best-in-class audio products at Microsoft. We use these facilities for designing products like the Surface, HoloLens and Cortana, that we take great pride in."
Products are tested by Microsoft's R&D in Building 87. This includes the new Surface range's speakers and microphones. Voice-based assistant Cortana is also tested here.
Microsoft Senior Engineer LeSalle Munroe explains this advantage, "This chamber gives us the opportunity to look for those really small signals that can have an impact to the end user."
The Guinness Book of Records, in fact, verified and certified that Building 87 trumped the -13db silence record of previous titlist Orfield Laboratories in Minneapolis in October 2012.
As an anechoic chamber it not only effectively blocks external sound but also muffles and absorbs all internal sound.
