hey i made my box and put silicone on the inside corners.. i think i want to add polyurathane sealant to the whole inside of the box, just incase it happens to get wet or something. is it alright to do that? or would it effect the sound in some way?
I wouldn't do it. At least not to the inside. If the box gets wet the wood will come apart before the speakers get wet. You could seal the outside before you carpet it. Or do the outside in vinal if your worried about spills (Uh hum your buddies beer). Just keep in mind vinal is not east to do, especially if you do it right and get the edges sewn.
but say if i do seal the inside, would it make a difference in sound?