This room, found at Orfield Laboratories in Minnesota, holds the Guinness World Record for being the world's quietest, measuring at -9 decibels. By contrast, the bedroom in which you sleep at night measures about 30 decibels. The room is called an anechoic chamber, which means there is no echo as it absorbs sound. Orfield created the room to test products to make sure they're not too loud.
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