On a United 737-800 or 900. One row ahead of wing. Measured at cruise:
97db C weighted. A three hour flight.
I’ll never travel again without good hearing protection!
I had foam earplugs, then wadded wet paper towel behind that, and for quite a while, my fingers holding it in.
Yes, I know about noise cancelling headphones. My BOSE ones died all by themselves without help.