yes , these are damping sheets
the most popular brand are "dynamat"
these sheets add , addition weight to body
which avoids from vibration which causes noise
in other words , it will hard to vibrate body after using sheets
how ever if you increase BASS OUTPUT LEVEL , some how it will sound again
these sheets cost very much
ask ENERLEVEL
cheapest solution , for controlling rattling is to stick 0.5" foam behind door wall
it will stop body noise very much , 1" will act more for stopping rattle
that body which rattles very much , u can stick sheets over their
and other , u can stick with foam