May I help some of the not initiated ppruners here about some basic facts about physics:
65 to 70 decibels are the volume you have at the moment in your office when you have your printer on or someone is talking to you in a normal voice.
Please read the Wikipedia article below:
Decibel scale
Landing traffic is never a noise problem, although some airport-neighbour-committees say so. "Look, there's an airplane - and if you listen there's also a sound". While the car going through the street is much louder.
Take off noise is a much greater problem indead. If those French Airbus-Engineers made it possible that the taking off A380 is at nearly office noice, then they have done a good job.
Dani