Re: Looking or the final part... The speakers...
Damplifier Pro will take care of panel vibrations, but it will not stop rattles and it won't do much of anything to block outside noise. More importantly, it won't stop the bad phase interaction from sound from the back side of the speaker coming through the door. This phase cancellation will make the midbass response sound weak, and not because the speakers aren't up to the task. You don't have to use the products I suggested to solve this problem, but the SDS solution isn't permanent and it attaches with velcro. This makes it easily removed if you need to service the door components. This will make more sense if you read the web site and look at the photos.
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