[Blue Dude]

Yeah, I made a wire exactly as you described and it made things worse. My sub doesn't have a three prong connector, so no help there. Everything is plugged in with the supplied power cords; no grounds are lifted. The sub is on a separate circuit from the rest of the equipment. Soon it will share a circuit, which may help.

I'll look into a Cleanbox, but I think I'll stick with this arrangement for the time being. I was afraid that having overlapping crossovers would mess with the sub output but it appears fine so far.

I'll rerun REW soon, maybe tonight, with the mains added and we'll see what it looks like. I haven't lived with this particular setup long enough to tell whether I'm satisfied with it as it is. There's probably room to tweak.

Thanks for the look!