I posted this before, but I am still confused by some of the replies. I have an Hartke HA 3000... Believe it is 300 watts into 4 ohms and 180 watts into 8 ohms... I was using one of my Epi cabinets - 1 x 15 older NY series.. If I raised the volume, only talking to 4 or 5 on the head, it would sound distorted and rattle somewhat... I didn't think it was a blown driver, because one of the drivers in my other Epi, a NY Series 2 x 12 had one, and there was NO mistaking. Sounded as tho I was playing In A Gadda Da Vida. Some said I was "overdriving" some said I was "underdriving".. I was looking in the cabinet, and while the speaker moves during play, this speaker was really moving in and out. I noticed this because I spent a lot of time peering into the cabinet during the show - something wasn't right. Also, I use active basses, but that doesn't seem to be it either. Now, this may sound dumb, but we were near a pool. When I picked up our set list, it was really damp from the pool. No splashing, just felt damp. Could the drivers have gotten damp?? Reaching, I know. Help!!