mrdecibel,
I wanted you to know that I ordered some damping pads from Amazon a couple of days ago, and it arrived yesterday. I started applying it to the horns of my Klipsch Epic CF 4s last night and was done in a couple of hours.
I had already damped them with the strips of grey putty that is used to seal leaky doors years ago when I first bought them, and that was ok, but I took that off and cleaned them very well and applied theses sheets made by Noico, which many amazon reviewers said was the best. Anyway, it's done and sounds better than before. I am seriously considering taking them out again and putting on another layer. These horns are so thin!
Thanks for the motivation. I've known about it for years, but I needed a little push.