I thought I would post this here for completeness as well in my other thread.
I finally took the time to take my screen down so that I could add the first step of my treatments. I did the usual front wall double layer of Linacoustic with a layer of 6 mil plastic between (I actually did two 3 mil because it was easier to deal with folded over). On the room-facing surface of the subs I added a single layer of Linacoustic and also put some scraps on the horizontal surfaces that my speakers sit on. You can see most of that in the picture, but it's hard to make out the front wall is also covered. I also took the opportunity to put a little black paint on my LCR drivers. There was a bit of the machined metal showing around the driver, and it would shine through the screen on some bright scenes.
My room design actually calls for a baffle wall with the large space behind used as a bass trap. But we're taking baby steps here. Here's a before and after of the room for reference.
Here are the before and after measurements of the center channel. I had to shift the measurements to roughly align. REW + Mac can be a little finicky, and the volume wanted to move around between runs for some reason.
I didn't make much effort to verify the mic was in the exact same spot for these two measurements. At some point, the front will end up with a baffle wall, but I was curious to see what the "standard" double layer Linacoustic approach does. Aside from the Peak and dip between 80 and just over 100 Hz, it's tough for me to say there's really any improvement. I need to run the rest of my sweeps on the surrounds, though. I suppose I might see some changes due to the rear surrounds pointing at the front wall, but they are a LONG way away.
I'm not sure I can really tell any difference in the sound. When I did my first listening test, I was initially very impressed. Then I realized my DDRC-88A was bypassed (no dirac live calibration), which for my room just makes the sound "brighter" and a 3 dB louder. And we all know the first rule of hifi, louder sounds better. Once I took that into account, A/B with and without my existing correction, I can't say I could tell much difference.
I'm beginning to think I'm tone deaf