Years ago, I subscribed to
Audio Amateur, and
Speaker Builder magazines (when I was doing some speaker design and building), and I remember a few things about power levels and sound pressure levels. I don't have any links to the magazine articles from back then, but this web page from JL Audio presents the information in a concise manor -
https://jlaudio.zendesk.com/hc/en-us/articles/217201737-Doubling-Power-vs-Doubling-Output
Here's a synopsis:
1.) A 1dB change in sound pressure level (SPL) is typically the smallest amount that the average person can hear - using pure tones under controlled conditions.
2.) A 3dB change in SPL is typically the smallest amount that is easily heard - with speech or music.
3.) It takes 2x the amplifier power to increase the SPL by 3dB.
4.) A 10dB change in SPL is typically perceived as "twice as loud."
5.) It takes 10x the amplifier power to increase the SPL by 10dB.