I had a rather alarming experience today with my JBL 590 speakers (which use the 2414H compression driver), where I am now getting "crackling" sounds from the compression drivers at high volume levels (music). Yesterday I finally integrated a miniDSP 2x4 HD into my system, and setup a 60Hz high-pass filter for the 590s. This is because previously I felt like the 8" woofers (580J) were the "bottleneck" of the system. When the 590s are run full range, they just don't have the output necessary to properly reproduce deep bass, and the high-levels of cone excursion had a predictably detrimental effect on all of the higher frequencies that the top 8" woofer is also responsible for (everything below 1.5kHz). The high-pass filter seemed to solve that, and combined with my subs using a matching 60Hz low-pass filter, it seems to have solved the "bottleneck". But today was the first time I was able to test that new arrangement at much higher volumes. The crackling only occurs at high output levels, and is clearly coming from the compression drivers. This is occurring on both speakers at about the same time (obviously dependent on slightly differing volume levels per channel as you would expect while playing stereo content). It does not occur at lower output levels. Have I simply discovered the next "bottleneck"? Am I now pushing the compression drivers past their limits? What exactly does it sound like when you push a compression driver past it's limits? It does seem very surprising to me that I have never encountered this problem before, as it's hardly the first time that I've driven these speakers loudly. Even though the woofers have often been the bottleneck, I'm not always playing content with that much bass where that would be an issue. And certainly this would be an issue during loud movies, which is what many use these speakers for, and where bass redirection to a sub is commonplace.