The minimum increase in volume which the human ear can perceive is 3 dB.
For reference, a 3db increase is twice as loud and requires twice as much amplifier power to create this increase. For people, however, a 3db change is the minimum noticeable change. It takes a 10db increase for a speaker to "sound" twice as loud. And this 10db increase requires over 8 times more power to create. 2x power for 3db, 4x power for 6db, 8x power for 9db, 16x power for 12db...
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Decibel (dB)
MJS_IraggiAlts reacted to brianG in sound perception