I believe the mighty Saturn V is mankind's loudest sustained noisy invention to date - not sure how it compares with the Thunderscreech but probably in some way less unbearable to those near Canaveral during launches.
Few years ago a ground running Griffon interacted with a ground running Merlin in such a way towards where I was standing 100yds away that moving was imperative - some sort of resonance focused the noise in that particular direction I guess. Both engines sound great normally but this was painful. Might have been the faux props fitted rather than the usual Dowty Rotols...