Any links to video guides on how to determine which specific areas need deadening and how to address them? (versus just saying to tap around ... )
I was hoping for the same thing, but sadly, not that I see.
If you find anything relevant please tell us !
It's very hard to measure before and after without some
sort of standardized test bed -- that we don't have.
The people who sell materials
will gladly sell us more of
whatever they have on hand than we need. A lot of that is
rather thermal insulation that doesn't mute as well as a simple
closed cell rubber with a very sticky backing. And none of
it is going to "
block" long wavelength (low frequency) sound,
that's futile, fat cement blocks would be more like it.
It's true that if you were to goop down every surface in the car
it WILL be more muted than before. Its just that, based on
my experience with industrial machines and sound studios,
it takes less than 1/100 of that to get 95% of the way there.
And BTW, tapping & pounding, and using a spectrum analyzer,
are time-tested practical methods. Remember the drum analogy?
If you find where to put it, one finger on the drum skin will work
as well as gluing a muting material over the whole surface.
.