The quietest place is the anechoic chamber of Orfield Labs in Minneapolis, USA, a laboratory so quiet it can drive you crazy and where the sound production is -9 db.
Perhaps you think it is a remote valley where only peace and relaxation reigns!
Considering that the noises usually heard at night in the bedrooms, those noises barely perceptible, have a volume of 30 db and that the limit of the human audible is 0 db you understand that in that laboratory the sound is completely absorbed!
The Orfield Lab’s anechoic (i.e. echo-free) room measures 3.6 x 3 metres and is built in such a way as to completely cancel out both the noises coming from outside and the reflection on the internal walls of the sounds produced from inside.
It consists of two chambers built one inside the other: the inner chamber, the heart of the entire structure, is insulated from the rest of the world by a layer of fibreglass and is 1 metre thick and its walls are covered with a curious three-dimensional synthetic foam upholstery capable of breaking up and absorbing 99% of the sound waves, all inside a third concrete chamber.
The room also “floats” on a spring system that cancels any vibration.
According to some tests, it seems that an average human being can’t last more than 45 minutes, such is the record of permanence attributed to the writer George Foy, a lover of silent places.
In this room, after your ear gets used to the total absence of sound, you start to feel your heartbeat, your lungs swelling and deflating, the blood flowing in your veins… in practice you become the only source of noise, a real experience of sensory deprivation!
Such silence can literally lead to delirium and mental imbalance.
Steven Orfield, in charge of the structure, explains that inside his anechoic room, once the lights are turned off, it is possible to experience the most complete sensorial deprivation: journalists and people who decided to challenge the room have resisted inside for a short time: some only for a few seconds; those who resisted a quarter of an hour went out in claustrophobia, nausea, panic attacks, auditory hallucinations.
But what is such a place for?
It is used to carry out clinical research on deafness, but also to study the sound of some products before they are launched on the market, for example the roar of some motorbike brands’ exhausts or the noise produced by new generations of washing machines and dishwashers designed to be operated at night.