i believe it definetly makes a difference in sound. No matter how acoustically transparent the stuff is, its still covinering the drivers. I have never left mine on. For dust you can blow compressed air on the drivers from a safe distance if it bothers you. you probbly wouldnt notice anything from the top of a QS8 but you would with something like fronts. if youve got young kids though, it might be better to leave them on.

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