no. as long as the total amount of air space for each sub is there than your fine. (i.e. each subs needs 1 cube and you have 2 cube total for your box than your good. my need a little bit more airspace to make up for sub displacement)
however there are some advantages to have a split chamber box.
ok well i ask because i have noticed when one sub is pushed in obviously the other is pushed out, but once the volume is turned to a certain level it makes a very mechanical sound. i didnt notice it before because they ere breaking in and didnt give them much power. anyways i thought maybe having them in the same chamber was to fault?