I was thinking of lining the inside of my enclosure with some fiberglass but I have a problem. Im not going to be able to get to the top of enclosure from the driver cut out (its already put together). So what would you recommend I do, I can get to the first three layers but the forth is not going to happen so should I just not put any up there or I could lightly stuff it with some polyfil. I all ready did a test to see if the polyfil would fall when its standing and it wont, but will it have a negative affect on the sound? Pics of the build can be found here so you can see what Im talking about..........
I wouldn,t worry about putting any polyfil in that area because the amount you would be adding would have no affect on performance.Stuffing a sealed box with damping material can have its benifits but lining the walls of a ported sub working below 80 hz is not really neccessary.Two much damping material in a ported box will adversely affect it's performance.
According to tests listed in Vance Dickensons Speaker design cookbook and others, stuffing a ported speaker up to 50% has a measurable, though slight, effect of lowering the resonance frequncy and extending the bottom end. This was told to me by someone on AVS. They also said that my design is ideal for this tweak since about 50% can be stuffed without any effect on the port to driver airflow. I have since lined the first three chambers with fiberglass about 1" thick and stuffed the fourth chamber with polyfil.
Thanks Steve, I went ahead and lightly stuffed the top. after I lined the the walls and lightly stuffed the top it does sound a little better. It seemed to have tightend up the bass not realy night and day but I could tell (every little bit helps right ) Heres some pics of the inside now I also started to paint over the last few days but ran out. I got about three coats on and it looks good where it stands but I will probly wait untill spring when I can get it out side to sand it down and spray the final coats on.