I just hooked up my brand new out of the box aw122t audiobahn 2 of them they are dual 4ohm voice coils when i first hooked them up i used one voice coil worked fine then i tried them in series/parallel and nothing then i tried series/series and it worked but i dont know if both vc are working is there a way to check but i dont see why it would work in series but not parallel can someone help out please oh btw these are ebay subs i have 30 days to return next time i know not to buy audiobahn