Noise is still noise. It's not so much where it comes from but when it comes! Noise after 10:30 pm wouldn't be wanted by many no matter which car you are on the train. Having a lounge serving alcoholic beverages in a sleeping car is not my idea quiet place.
You are reading too much into the Park Car being a noisy “Bar Car”.....It is not. You’ll find most passengers just having a quit conversation over a drink. Last call is at 10:30pm and if you are worried about someone talking in the corridor as they pass your room in the Park Car......just remember they would also be walking past the rooms in the adjacent Manor or Chateau Sleepers until they reached their own room. It’s really a non issue.
Two years ago I had a Bedroom in the Park when VIA offered entertainment. I spent most of the evening in the Bullet Lounge enjoying it but when I did return to my room.......I really couldn’t hear anything over the usual track noise and ventilation system. Again.....a non issue and besides the entertainment ended around 10pm.
VIA (&CN) have operated several types of sleeper lounges over the years including full lounges and I don’t remember them being particularly noisy. But what I can remember is back in my younger days and riding the “Scotian”......the evening train oat of Halifax for Montreal and partying into the wee hours of the morning in its Coach-Lounge.
Another Lounge noted for its party atmosphere was “Le Pub” on Amtrak's Montrealer......and in particular on Friday nights out of Penn Station with a ski crowd aboard heading for the slopes in Vermont!