Here’s my room graph.
“Y axis is reverberation time in milliseconds, X axis is frequency. Ideally the curves are flat lines at about 400-500 ms. This is as close as I’ve ever seen to even in any space I’ve ever measured.” said my good friend and professional sound engineer. I found the last sentence quite hard to believe, but he’s not known to mess around with such statements.
Anyway, the orange line is pre-treatment and the blue is post treatment. He used a very expensive sound level meter and popped balloons with his assistant to get these measurements. I have another big thing of info, but this is the clearest. Anyway…wanted to do what I said I would do and am a very big believer in treatments and knowing what the heck they are doing, or potentially not doing, in my listening room.