The original post: /r/todayilearned by /u/Few_Loquat_4217 on 2024-12-01 18:27:54.

Original Title: Today I learned that sound can be minus decibels. The quietest place on Earth is Microsoft’s anechoic chamber in Redmond, WA, USA, at -20.6 decibels. These anechoic chambers are built out of heavy concrete and brick and are mounted on springs to stop vibrations from getting in through the floor.