Right BA, externally nothing beats the whisper jet, BAe 146/ARJ. Internally, however, it is quite avarage.
It all depends on where you sit.
For quietness hardly anything beats the front of the MD-80 or -90. (I assume that the 717 has the same qualities, but haven't experienced yet). But they are really bad in the far back. Even the DC-9 is very pleasant up front, but a quite extreme pain in the back, especially when you experience a crew who doesn't care about engine syncronization.
The only thing worse is the back of a 737-200 during take-off - pure thunder, but unlike the MDs it calms down to bearable levels when it accellerates to speed.
A few years back I invited a friend - a cityzen of the former Soviet Union - on a trip to Paris on an AF 732 - sitting in the back. He had flow hundreds of flights on all the most noisy Russian airliners except the Tu-104, and he was eager to experience a "quiet" western plane. He was shocked, he had never heard anything as loud as the 732 taking off. We flew back home on a 735, a very different story.
The 757 is really pleasant all way along the cabin, but pilots complain that the cockpit is rather noisy.
But who cares about a little noise on the short jumps? In between the engines on a DC-9 is a little too much for me, but otherwise what counts are the long distance intercontinental flights. Strong noise for many hours is tiring, but otherwise it is just pleasant to know that the engines are spinning, isn't it? Try a Caravelle, and it will not leave you in any doubt.
Best regards, Preben Norholm
Always keep your number of landings equal to your number of take-offs