Yes, the difference with and without the EQ is night and day. My SMS replaces a BFD which I was using for about a year. I would never go back to using a subwoofer without an EQ of some sort. In my opinion, a sub EQ is a must have.

--------- NEC 42" Plasma Axiom M60s(x3)/QS4s/M22s Denon 3805/3910 Outlaw 7700 SVS PC-Ultra