I think the ERJ has a more quiet cabin than the CRJ. (Not that this matters, unless your deadheading or something) But the CRJ was alot louder in back I feel. Although when we became airborne the front row of the ERJ was very loud. But it doesn't sound like an engine, it just sounds like wind that is very loud. I'm Not sure how to discribe it. I guess there is just something about the ERJ that I like more.