Now you're thinking with decibels

Learning to think in terms of decibels

+10db is: 10x the acoustic power and 2x as "loud"
+6db is: 4x the acoustic power but only 1.5x as "loud"
+3db is: 2x the acoustic power but only 1.23 as "loud"

Some implications to think about:
a 1-2db change in volume is barely perceptible
doubling amplifier power does not double loudness

I learned this concept as "perceived loudness" back when I worked at Sweetwater.