.................Once airborne, my guess would be that regardless of engine supplier, the noise/vibration when seated in line with the similar sized fan sections will be much the same. Post acceleration phase, I suspect perceived noise is more airconditioning/pneumatics than engine
- although tied somewhat to significant thrust changes.
I tend to avoid twins transatlantic, but last year I shelled out for "Club" flat bed MCO LGW on a 777 service, and was mildly puzzled when just a shade under the 24 hours ahead limit I checked in online to find only the back row available. You guessed it - the regulars knew it was exactly in line with the fans. Won't get caught like that again!
Eventually, as the weight and power settings reduced - maybe about an hour from top of descent, the waves on the top of my coffee dissipated somewhat.
Whichever engines, the 777 fans are huge, so it's hardly surprising
( I suppose )
Still, mustn't grumble. Half close your eyes and you can imagine it could be 1958 on a BOAC Britannia.....
What goes around comes around......