I couldn't reach the screens on my 604's for some reason...theres a metal piece with some small round slots in it just behind the phram and I couldn't figure out how to move it. So all I did was the Markwart suggestion of removing the loading caps and felting the inside of the rear covers. I used the peel and stick loop part of some velcro I bought and covered the whole inside of the rear cover. It has excellent stickyness so it'll stay where it was put. I will admit it was close to a vast improvement in clarity and soundstaging although one other point was that when I opened up the push on connector phram the red dot was by the terminal on the right side of the phram and when I opened up the other speaker phram the silver L1 was by the left side terminal of the phram so for once in their life both the red wires from my crossovers are hooked to the proper terminals. I'm still trying to dial them in but I like how much nicer they sound now. Thanks Jeff.