Actually, your ears are pretty close to logarithmic in perception so a difference of 20-40dB is a lot less than you might expect. Below a certain level ~40dBA i

Actually, your ears are pretty close to logarithmic in perception so a difference of 20-40dB is a lot less than you might expect. Below a certain level ~40dBA it's hard to discern, because other noise sources dominate, but in a perfect anechoic chamber or alone in a cave you can hear significantly lower holding your breath. I've usually heard about sound Pressure levels at a specific distance (eg 1m) where 20dB is a 10x increase (not 10dB) while for sound POWER levels you're correct 10dB is a 10x increase and power is closer to our logarithmic perception. Human hearing easily covers (and can distinguish loudness) over 5-6 orders of magnitude with ~1-3dB resolution. 0dB is the limit of a young ear 10dBA is normal breathing at 1m 20dBA is a soft whisper at 10ft 30dBA is a soft whisper (1m) 40dBA is a very quiet library (no distance) 50dBA is a coffee percolator (at 1m) 60dBA is normal conversation 1m 70dBA is a TV or a toilet flush 1m 80dBA is an alarm clock 1m 90dBA is a blender or shouting 1m 100dBA is a circular saw or motorcycle 1m 110dBA is a loud concert (no distance) or leaf blower (1m) 120dBA is an ambulance siren or jack-hammer 1m