how to acoustically treat a concrete wall?

sadf

"I have a concrete wall made up of 3, angled panels (52", 50", 52") and a basement window in the middle of the center panel. I was wondering how I could acoustically treat this concrete without building a wall? (studs & drywall). I was considering covering the wall with panels build of plywood, cloth, & the stuffing you put in blankets in between... I would evenly space them out so it doesn't completely deaden the wall... Thoughts? Thanks." Why not just build some panels out of oc 703 or mineral wool? "EDIT: I also have a question about the basement ceiling... It's a typical basement ceiling, support studs showing, pipes hanging down every which way, and to do a drop-down, the ceiling would be shorter than 6 feet.. so not really an option. I've read/thought that putting cloth up would attract bugs, get musty, moldy, and smelly... So are there any other options? Should I leave it alone? Thanks again." I would stuff the rafters with fluffy fiberglass. Not sure why you think you would get bugs or get musty, but if you think so you can skip that part. The fabric is really only for looks. Glenn