American vs British laughtracks - is there a difference?

If I’m watching a comedy on BBC America, or a British comedy on PBS, it sounds like the laughtrack is much louder than what you would find on an American sitcom. To my ears, it seems seems like British laughtracks have a different sound (more like “arr arr arr” compared to an American “ha ha ha”), and they stop quickly, rather than ramping down.

Are my perceptions correct?

I’ve noticed this too. I think it’s partially that the two audiences do actually laugh with different sounds, and find different types of humour funnier. Maybe it’s a cultural bias, but I also find British ones to sound more genuine - I find the cut-and-pasting of laugh sounds on Friends to be infuriatingly false.