[best] - Loudness Sones

Extremely quiet. Similar to a whisper or a quiet library. You’ll hardly notice it’s running.

A is a unit of perceived loudness . It was created by psychoacoustician Stanley Smith Stevens to answer one simple question: How loud does this actually feel? loudness sones

Next time you see a product claiming "Super quiet: 50 dB!" ask for the Sone rating. A 2-sone fan is a peaceful retreat. An 8-sone fan is a jet engine in your kitchen. Understanding the difference saves your ears—and your sanity. Extremely quiet