I have dual SB3000 subs paired with my Revel F226BE mains. My volumes are 13 and LP is 120 to assist with the weak low end of the Revel 6" woofers. I sometimes temporarily adjust the sub volume according to the source material. My speakers are close to the rear wall but many feet away from side walls. The subs sit along side the mains and are facing around 45 degrees to the sides to keep the rear wall from acting like a bass resonator.
What are your exact settings for volume and low pass filter on your SVS sub?
With my ATC SCM40s—passive—I’ve set the volume on my SB3000s at 20 and the low pass filter at 58. The speakers go down to 48hz at -6db.
I have no frame of reference and feel insecure about my selections. It would be great to hear from other people about what works for them, although I know that it’s always apples and oranges because of the room factor, the amp, the different speakers, and all the rest.