[migle]

Very nice picture!
I never did a faster trip in the back seat, so I don't know about noise there. In the front, it's a quiet car. Like happens in the Prius, when you remove the engine noise, suddenly everything else seems to become louder: road noise, then the wind noise crazier than you ever heard.

Don't you find the wind noise incredible too?

One thing is certain, after a long trip, you don't feel as tired, and your ears don't feel the same as after a long 120km/h trip on a silent ICE.

PS: humans can't measure loudness with the ears. It's all relative. The incredible sound proof windows that remove all street noise during the day, are incredibly sound-permeable in the middle of the night.