Anyone ever use something like dynamat or eDead inside a sealed box? My tweeters in my home stereo have a tapered tube behind them to cancel out the sound from the reverse side of the driver cone, so all you hear is the front harmonics.

go to a craft store and get some pillow stuffing. Remember that this also tricks your subs into thinking the box is slightly larger than what it really is.

Yeah i know all about that, but what about using sound deadening material to help cancel out the sound in the box even more? I guess it wouldn't be too hard to test out.

useless unless you're using a sheetmetal box. 3/4" MDF will do.

I had a similar idea a while back, but i never got to test it out. I doubt that sound deadening would be any more obsobant than box stuffing, but like you said it wouldnt hurt to test it out

that won't work. the box needs to look bigger to the waves. they pass through the insulation, taking longer, so the box looks bigger. with deadening material, the waves are the same length

Im not so sure thats the reason, i dont really think that there is a real proven reason why, everybody just knows it works