• Date Posted:

    21 — 09 — 2018
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The Silent Room: Anechoic Chamber at Orfield Laboratories

Whether after a long day with talkative colleagues, a congested commute, or a weekend with the family - peace and quiet is an essential oasis. It’s not always that easy to find.

Unless, however, you make the trip to in Minnesota’s capital city. Keeping quiet in the south Minneapolis is Orfield Laboratories, home to the worlds only public anechoic chamber - a near perfectly silent space designed to completely absorb soundwaves. Anechoic chambers exist around the world, but mostly hidden away from prying eyes and ears.

A room of sheer silence to relax and unwind in may sound perfect, but things inside might not be as serene as you may hope.

In the chamber things can start to get a bit eerie, after closing the door and letting the last of the outside audio sink into the walls, your ears start adjusting. This often starts with “ahh, silence”, though this is quickly followed by “has my breathing always been this loud?”. Then your heartbeat starts to creep up on you. The more your ears adjust, the more you hear. Move and you can hear your bones creak off one another, the blood running through your veins and arteries suddenly thrums in your ear; some even hear scalp creeping over their skull. For some people the chamber can be too much; we’d at least recommend sitting down.

Removing the audio cues that we used to in everyday life - such as your footsteps – it can become very difficult, if not impossible, to keep balance. For many, just a few minutes in the chamber is overwhelming and it’s considered impressive (if pretty ill-advised) to stay in an anechoic chamber for over 45 minutes. But, for the few that do find peace, 45 minutes is not always long enough.

An anechoic chamber is not just a room, it’s a room within a room, isolated and sealed off from the outside world, with a suspended grated platform to allow for standing space. The floor is covered in 3-foot fiberglass ‘spikes’; the same with the walls and ceiling. These spikes are where the secret lies: unlike a flat surface that would reflect sound waves back into the room, the spikes are designed to trap the waves bouncing between them until they lose energy and disappear, so the longer the room is sealed for the quieter it becomes. Some anechoic chambers are capable of removing up to 99.99% of sound waves, registering an astonishing sound level of -20.6 dB.

Anechoic chambers exist in all shapes and sizes; from a small shoebox (these don’t have standing room) up to spaces large enough to fit aircraft in. All different kinds of products - from medical devices to hard drives - are subject to noise testing within these chambers. Auto manufacturers use these rooms to measure and finetune engines; electronics specialists aim to minimise the sound produced by their devices, doing the world a favour by trying to eliminate the noise of a loud laptop. Even NASA use the conditions in anechoic chambers to train astronauts; an anechoic environment is the closest we can get to the dead soundscape of space. 

Though RHA headphones aren’t made specifically to be used in the empty void of outer space (yet), all of our in-ear headphones are taken through their paces in these silent chambers to tune the frequency response of the driver and to perfect passive noise isolation.