Rear wall absorber question for small mix room

Hello John and everyone! Before I post my question, I'd just like to say that I've learned a great deal on this forum over the past few months, and I'm amazed that there's such a great resource on this topic available. Thanks to John and all the regulars for helping me learn -- I don't know where else I could possibly had access to half as much information! I definitely have a much greater knowlege of, and appreciation for, the black art of acoustics and studio design. So, now on to my question.... :) I'm trying to plan a redo of my home mix room, which unfortunately is both small and rented. It's 10'6" x 11'3", with an 8'3" ceiling. I have a good idea of what treatments I'll be putting in (John's DIY side wall absorbers, probably on casters so I can get around them, 703 in available front corners (or maybe slats instead,) probably 703 over the front wall/ceiling corner, and a 703 cloud over the mix position.) Except for the rear wall, which is where my question comes in -- does this thing look like a good idea? (see pictures) I'd have two of these side by side, so there would be a false rear "wall" that runs from the floor just about to the ceiling, and for most of the width of the room. My intent is to make my treatments as mobile as possible, since it's a rental; hence the freestanding rear-wall thing. The back part of it, where the hangers are, will be up against the (actual) rear wall of the room, but not attached in any way. This way the 703 is spaced a foot off the back wall to help it absorb lower. I'd go father out, but I don't think I'll have room. Does it make sense to put the hangers in back there? All the designs I've seen using hangers has them sealed off somehow - is that necessary for them to work, or will they work in an open design like this? I could make them as tall as 6-7', so will that work OK even though they can only be less than a foot wide? (for the ones facing sideways, anyway) I'd love to hear your comments and ideas about this idea. Finally, my apologies about the picture quality -- I'm using Appleworks as my drawing program, so bear with me! Things are generally to scale, but the furniture in the studio layout is not; I can do that and repost if it would be helpful. Thanks in advance! Dan

just the frame for the rear wall absorber:

mix room layout:

Are you speaking of the back of the cavity sealed off??? With a hnager in it??? If so, dont even waste your brain worrying about it. Remember the hanger is a loose hanging absorptive device to absorb/trap bass. Your design is an excellent design. it will work wonderfully. Only change I would make (because i am Dr. Frugal) is to change your front layer to useing semi-rigid Rockwool covered in fabric.

Hello Bryan, thanks for the reply! Yes, I was concerned about whether it'd be helpful to have the back and/or sides of the unit sealed for the hangers to work correctly. Glad to hear that's not the case. As for the 703 vs. rockwool, thanks for the idea -- I'll have to see what's available in the area, I'll be happy to get whatever I can, and if it's cheaper, so much the better! So, for the hangers, I'd like to get as much low bass absorbtion as possible, since the room definitely has some issues down there. The low bass hangers John describes would be wider than I could fit in this space, but I could make them longer if that would help. Should I just shoot for hangers of roughly the same area as John's 1.8 m x .5 m hangers, maybe 6-7' x just under a foot? Or is there a better way to do it? Thanks again, Dan

You will be surprised by how much bass trapping you will get by doing your design without the hangers. :) The hangers just add the extra ooomph!!!

Great, I'm looking forward to having a better sounding room! Thanks for your help, Bryan. I'll just make the hangers as big as I can fit them into the space, and maybe vary the sizes a bit. Thanks, Dan