I am making a dual 10 inch sealed box, my question is , is it better to have 2 seperate selaed chabers (ie. a divider in the middle of the box seperating the 2 speakers), or just have no divider and the speakers charing the same space?

 

Every box I have ever built has been 2 separate chambers. That way you don't have to worry about the 2 subs fighting against each other due to one of the many things that might cause such a thing. I believe the way to go is to build it and seal off the 2 chambers totally independent of each other.[o|o] I am not an expert, just about 15 yrs of playin around with stereo stuff to stand on. Hope this can help ya.,,,,,D-MAN

 

That being said there has never been a documented case of a negative affect. But bracing will need to be more substantial and extra precaution to avoid standing waves in the twice as large free space.