Nice to see another Polkie. I have RTA-12c mains, CSI-5 center, and 2 pairs of RC-85i's for surrounds.

That must have taken a lot of tweaking. If not, you are lucky.

I spent the best part of a weekend getting the perfect response line. Later I realized that I had done the whole thing with the door of my home theater open. It took me months to find the time to try again.

Looks like a great blend with your speakers. I have a 100Hz dip that doesn't seem to go away.