Thanks Bit.
I almost immediately heard things in my reference tracks that I've never heard before with such clarity, even with the new focals before I got the treatment in place. Kick drums for example, before there was nice definition to the bass, but it was mostly the kick transient and the bass, now I can actually hear what kind of beater used, the quality of the kick, some have a woody quality to the bass that was covered up by my room adding extra bass before. Reverb tails also stands out much more in dense tracks. It was the large broadband absorbers that really made a difference for the low end.
One of my favorite reference albums is "Jazz at the pawnshop" (yeah metal guy liking jazz, how about that hehe), it's like sitting in that club now.
@Jeff, no worries I'll keep the NS10s, they are so brutal for checking mixes on,they basically have all the problems that one needs to worry about, not much low end, brutal midrange and doesn't go very high. Sometimes I also work at friends that have a set, so it's nice to have something familiar to check mixes on.