I gave up on trying to integrate the 500s with the active LFRs in the living room. That room's dimensions simply can't support extra low frequency bass.

So I moved the twin 500s into the basement. It took some math, but I got them integrated with the M100s and the 800. I can't phase align them perfectly with the QS10s. They are within 5 degrees of one QS10 and 7 degrees within the other and I call that good enough. There's nothing I can do about it.

I thought I had great bass and sub-bass, and I would have never believed it if I hadn't heard it myself, but the difference is astounding. Not only is the bass even all around the room, the tactile feel of it is incredible even at lower volumes.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated