I too have the same problem of mixing in an untreated room. I’ve been doing all my mixing using headphones recently. i live in a townhouse that is close to a major highway so mixing at lower levels doesn’t really work for me unfortunately. I’m looking to upgrade to a better set of headphones soon, and hear about the sonar works plug in on one of Dezz’s podcasts. He seems to like it quite a bit, so I was looking to give that a shot. I think that if you get to know the equipment you are using you can get some good quality mixes, even if it’s not top of the line stuff.