Thanks for your suggestions. I did remove most of the felt inside, which was a lot but I was surprised it did not seem to make much of a difference. I'm trying to stay away from adding tone controls but I think I need to. The drivers are already broken in, I did that before I mounted them, I ran them for 50 hrs. with various music program at moderate levels. I would like to experiment with a couple different port lengths. Currently I have 3" port 3" long. Any suggestions? Do you know of a stand alone unit that only have tube tone controls? Thanks again for your help, Pete