Sub bass is unidirectional and midbass is 50/50. So it will sound like some freq's are coming from the rear instead of your sound stage. Meaning your system should sound like a well set up home system would in stereo not surround sound while listening in a chair or couch sitting in between the speakers and back from the speakers at equal distances. You want your system to sound like your at a live concert. Meaning all sound comes towards you not from in back of you.
Unless you saw Pink Floyd's "Animals" tour. In the 70's synthesized quad was the thing! It mimicked a quad home system.
It was bogus! That's why there's neither anymore