Loudest Sound Ever?

Lumen Field (Centurylink Field), Seahawks home games: sustained SPLs 125+ dB. 
I’ll watch at home thank you. 
Once in my youth I fired a 357 Magnum, having forgotten to put on ear protection - took two days to hear correctly, and likely did some long-term damage. 

1969. South Vietnam. B52 strike about a mile too close to a F0 I happened to be occupying. "Shook me all night loooooong. "  Diz

The guitar solo during Comfortably Numb on the Roger Waters The Wall tour. At the Boston Garden.

Hundreds? Thousands of miles away. At 160 miles away, you would have been left without hearing for the rest of your life. Anyhow, what an interesting way to advertise a Bluetooth speaker. We had a chuckle over that.