When you make a speaker box will it sound without the wood piece in the middle for the Sub can have it on Cu/Ft. Will it loss sound without the wood piece are it will be that same?
You won't lose sound without it. It will sound the same as if it were an open box, with the added benefit of getting more bracing. Plus, if one sub blows in an open box, then the other one essentially sees twice the air space, which will throw the sub into higher excursion levels and risks damage at high volumes.
I'd go with the divider also but if your system is set right and both subs are working. It will sound and have the same output with or without the divider in the middle. But like they said it will brace the box better and if one goes out the other will sound bad or blow.
