I'm getting my sub dialed in, it has a crossover that I use, as my pre-amp has pre outs, vs. a dedicated sub out.

After many adjustments, sounds pretty good, but I'm still going to move it elsewhere.

My friends all point to the mains saying "it's coming from there" (sounds like it to me too), I nod and mention they're capable. I then tun off the sub and watch their reaction.