I almost said "padding" but figured some would assume I was talking about the L-pad for the tweeter. I really like my Avatar B212; I think for the money, you really can't do better. But I also think it sounds a little boomy. I.E. underdamped. I peeked thru the vent w/a flashlight. I saw two pieces of really thin carpet padding (looks like it) stapled to the rear wall of the cab. Don't know if there's anything on the sidewalls. Whether I use my Spector or my SX, front/rear/both pups, the cab sounds boomy. I've tried tweaking the bass on my amp but that takes the booty out of the sound. I'm convinced (to my ear, obviously) that the cab is underdampened. Has anyone experienced this and if so, have you done anything about it? Added more material to the cab? Thanks.