DOOR sounds like a an OLD Pickup TRUCK door on closing

[JoeFromPA]

Subaru simply made all their new cars have framed windows (going away from a gorgeous styling exercise) and since then, the doors sound solid enough for that market.

Interesting side note: When my 08 legacy gt has it's window up and door slammed, it sounds a bit less than satisfying but not bad. When the window is DOWN and the door is slammed, all those fine polymers on the arm-rest buzz visibly as the door shakes in it's frame.

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Lexus goes to extreme lengths to make sure a consistent experience is given to it's customers. One of Lexus core strengths is producing the exact sound experience the customer desires....silent running, lack of noise, excellent acoustics in the cabin. It makes for a dis-engaged, floating experience IMHO, but they do it superbly well.

Your boxster door will never sound like that. It's a frameless door slamming into convertible top and it DELIBERATELY leaves the top window door when the door shuts, before raising it. This means you don't get the air sealing effect that sometimes prevents door shake.

However, it sounds to me like your boxster moves beyond the latch which causes a bit of movement and noise. This makes it easy for the door to shut all the way, but creates more rattle. I'm no expert in this area, but there are ways to reduce the movement once the door enters the latch.