I was giving an example. I will give another one: A whisper has around 20db, a washing machine which is way louder than a whisper, has around 70db. The washing machine sound is more than 4 times louder than a whisper because the decibel scale is logarithmic, which means that the db scale is not liniar like meters. For instance, 2 meters + 3 meters = 5 meters, 40 db + 40 db are less than 80 db. Maybe the liniar mode of the app converts the logarithmic scale to a liniar one, where 40 db + 40 db equals 80 db, not less.