It's not the sound it's the work involved in making it look good. (The sound is going through the speakers not the back of the enclosure). Fabric is glue and stick. Paint is sanding smooth any surfaces, filler, sanding, primer, more sanding, more primer, more sanding, paint, sand, paint, (x?) maybe clear. It's 15 minutes to an hour's worth of work vs hours and days worth of work for something that most people will never see, unless you want to show them. If it's in the interior, then carpeting blends in better, and might be a better look for you. If you do fiberglass you might want to show it off, and paint, but you are already spending a bit of time anyways.