[Radioroslyn]

If you've done any web research on the 116X you've probably seen this:  http://www.tuberadioland.com/philco116X_main.html  Excellent write up and mentions the ac. There has been a lot written over the years about the ac.  Some have said it's junk science or that it's just sale gimmick. At the rear the center of the cone is fitted with rubber strap to dampen the cone's movement. A lot of these look like they melted sort of droopy. Someone wrote a piece about replacing the rubber strap with a section of plastic wrist band. It looked ok but not sure if it would respond in the same manner as the rubber would have. As for the ac's in general personally I don't know what the performance is like with or without I've never done a test.
I must admit that I have thought of removing the two small ac and replacing them w/a pair of tweeters.