Grill Cloth Subwoofer Cover

So, my girlfriend decided that the sub in the living room was an eyesore and she decided on her own to do something about it. She purchased some grill cloth from Parts Express and made a cover for the sub and put a silk fern on top of the sub to further hide it. It covers the sub fairly well and the silk fern takes away the hard look. She made the cover so that it covers three sides of the sub and does not cover the amp side of the sub which faces the wall. The fern on top of the sub basically holds the entire thing in place and keeps it from rolling off. However, I think the sound has lost some of its oomph and she says it sounds the sme. I think the loss of oomph is in my head.

Anyone else do something like this?