Polyester improving bass boxes

[AngloScot]

I've heard that putting polyester inside a bass box increases the loudness of the bass. Is this statement true and if so does it increase the bass by a noticeable amount? Is it worth stuffing an old football top inside my bass box to make it louder?

[ezapf]

     What you are referring to is the damping material inside the bass box. It is a  material added to the interior of a speaker enclosure to absorb sound and reduce out-of-phase reflection to the driver diaphragm (cone).

     An old football top is not what you want to use. Usually acoustic fiberglass, polyester batting, or Polyfill is used in speaker enclosures. If you have a factory made bass box, it should have the material installed.

     Damping material, in effect, can make the bass louder by removing out-of-phase reflection. It probably will not be noticeably louder but what you may notice is a cleaner sound.