The quietest laboratory in the world

In the depths of the 87th floor of Microsoft headquarters in Redmond, Washington, USA, a special hardware lab was set up. The background noise was only -20.6 dB, which is considered to be “the quietest laboratory in the world”. .

Previously, the quietest place on Earth was considered to be the absorbing darkroom of the Orfide Laboratory in Minneapolis, USA, with a noise level of only -9.4 dB. But this lab deep in the 87th floor of Microsoft headquarters has clearly broken this record!

Can hear the sound of my stomach squirming
The quietness of the Microsoft lab makes us unimaginable. It is said that in the Microsoft lab, we can even hear the sound of our heartbeat, blood flow and gastrointestinal motility. This is not an exaggeration, because the human hearing limit is considered to be 0 decibels, and the background noise in this laboratory has reached -20.6 decibels. The air molecules collide with each other at room temperature in a non-vacuum environment, and the noise generated by collision is only about -24 decibels.

The world we live in is full of sounds, and the noise can be controlled below 0 decibels, showing that the sound insulation effect is remarkable. It is said that even if a jet plane is taking off outside the building, we can only hear some whispering roar in this soundproof room.

Full set of special isolation design
How do architects achieve this level of sound insulation?

According to reports, the single site of this laboratory took 8 months and it took another two years to design and build. It is located at the center of the 87th floor of the Microsoft headquarters building. The six sides are all 30 cm thick concrete structures, and it is almost suspended – the top of 68 damping springs mounted on separate shock plates, which means Any noise around the building will not have an impact or shock.

The space inside the laboratory is a cube with a length, width and height of about 6.36 meters. The six faces are covered with sound-absorbing foam wedges that help absorb any sound generated from the interior of the room. Its floor structure is also very special, it is a mesh formed by the traction wire rope used when the fighter landed on the aircraft carrier. The air supply, fire-fighting equipment, cable equipment, etc. in the room are all specially insulated, plus a special sealed door, but to achieve extreme quiet.

What is the laboratory used for?
IBM has also built a “silent laboratory” in Zurich, Switzerland, for nanotechnology research, because these studies are carried out on the “nanoscale”, the magnitude is very small, any vibration of the sound will make research The object is followed by jitter, so it is difficult to conduct research in a normal environment.

In addition, you can test the speakers and check the computer noise – from the power supply to the cooling fan and the sound of the display when the backlight is added. This Microsoft lab is mainly used to test the sound produced by electronic devices while they are in progress.

Recently, Microsoft engineers began using the lab to train their intelligent voice assistant Cortana (the world’s first personal assistant) released by Microsoft. The silent environment of the laboratory provides the most ideal test conditions for this type of test.

Microsoft has also received applications from a number of biomedical institutions, hoping to use this silent laboratory to study diseases such as schizophrenia. But Microsoft seems reluctant to accept such medical experiments.

In fact, some visitors said that they stayed in this Microsoft lab for a little longer, and they felt very uncomfortable, with symptoms such as tinnitus and dizziness. Some people want to go out after a few seconds here. At present, the longest stay in the time is only one hour. Previous studies have shown that in extremely quiet environments, even normal human brains can produce hallucinations. Even if there is no hallucination, when we stand in such a space, listening to the sound of joint friction, the sound of blood flowing, etc., it will not be a comfortable experience.