Correct. dB isn't a linear scale! 71dB is louder than 69dB by far more than (say) 69dB is louder than 67dB, etc.
In fact that was one of my considerations when I opted for the Dunlop Sport BluResponse over the Continental ContiPremiumContact 2 MO that I previously had.
That said... while the difference between 69dB and 71dB is noticeable, as others pointed-out the EU rating is for noise outside the car, not inside.
It is quite possible that the noise inside the car is in fact lower to such extent that the difference may be unnoticeable.
My own experience is that the biggest differentiator is the road surface.
Only time I ever really notice tyre noise is on the concrete stretches of the M25!
Yes, but they're 71 db noise rating according to Costco, and 70 according to Camskill, so I'd best buy them from Camskill...
I'm spoilt for choice; it's a nightmare, and my brain hurts, Brian...
Michelin do the Cross Climate in 245/40/18 which gets a 69dB rating too, or Pilot Alpin @ 68dB. I guess it comes down to what matters most - safety and good performance in different conditions, quietness, or cost etc.