I am using REW on a Mac with an RS-33-2055 through a MOTU 896 converter, sound played back through a pair of old Mackie HR824's. My room dimensions are 7'4" wide, 11'4" long and 94" high. Basically a finished shed. Untreated as of yet, but full of other stuff. I am wondering about the waterfall plots. Is it possible for the decay to continue to climb throughout the time window? I know my room is bad, but from the response, it looks like its about 15db louder AFTER 500ms. And that's just from 20-200. It's much magnified above that. Can this be right? or am I doing something wrong that someone here can see from the details I've given?