27db at the chair.
For reference.. take away what you will with the final number.
20x24x8 fully treated dedicated room separated from house, concrete slab, separate transformer , oversized air ducts, closest neighbor is 1/2 mile away, 8" on center staggered stud room 20 amp dedicated lines, fully corning/ rockwool , GIK, Vicoustic, etc blah blah....
People say when they walk into the room for the first time that it's deceptive because their entire hearing kind of folds up and freaks them out till they get used to it. I don't know any other folks with treatment to degree but it can be maddening quiet. The apps are good for reference but every time accuracy and technique.... with numbers so close to mine that I am seeing I defiantly have to wonder, but either way for me the room is everything and people might be surprised how much some of that expensive gear has nothing to do with the final sound outcome. It makes an amazing room all around and I find solace in it when things get coo-coo.