There's a few things at work here...first, 2 inches from the wall is far too close for ideal setup.
Second, A sub will still play lower than a 7inch drivers can, though maybe not with the same accuracy above 30 Hz or so.
Also, consider that one 12" woofer has almost as much area as SIX 7" woofers combined. I wouldn't expect most multi woofer systems in that price range to really deliver that gut-wrenching bass. Maybe you have high expectations?