I hate to resurrect an old thread, but........ I have an Echo 18 that the woofer went out shortly after receiving the unit, back in 2016. After Jeremy bailed and I couldn't get a replacement under warranty, it sat for awhile. I moved and just now got around to replacing the woofer. I pulled the defective unit out and there isn't an ounce of poly-fill in the cabinet. Has anyone else done maintenance on their sub and come across the same thing, is this the way all were built or is mine one of the last units out the door and no one cared? I discovered that Paul Pierce built the woofers for Reaction and he was extremely helpful in building another HT unit to meet the specs of the original.