Can I recomend you doing those tests with the mini models but with normal side only reflection? We all know that having no reflection is a bad thing, but that doesn't mean that having the angles and all that would contribute more than normal and floor reflection only enough to make a difference to deal with all the hassle. Sorry if I sound like an asshole party pooper I just wanted to bring it to your attention before you go through the trouble of making a full sized chamber that might end up not really making a big difference at all. Goodluck.