Rokosz

I think I may.......have an idea of why the tweeter is being "muffled." A while back I bought the same speakers and encountered the same issue. The gap in which the voice coil "floats" is filled with ferro-fluid to help cool it down. When the liquid portion of the ferro-fluid dries out, the remaining "ferro" looks like microscopic iron filings. That stuff gunks up the slot and can even prevent the coil from moving at all. You still have good resistance reading because the voice coil is still there and intact. Just as the liquid evaporates, the substance becomes more and more thick and movement preventative.