I NEVER want to hear my neighbors in bed! Nor do I want them to hear me!
I would build a sound box and disguise it as a big upholstered headboard. Since you are handy, here's how:
Buy an egg crate foam bed pad. Build a frame for it. Attach the frame to the wall. Upholster the frame: Use a bedspread you like, or drapery. Add buttons to create tufts, gather it if you like. In your space, I'd probably build the frame corner to corner and insert two bed pads. Attach it to the wall. This should reduce sound transmission much more than any internal wall configuration and give you lots more privacy.

You can buy rolls of phonic insulation about 2cm thick and then cover this with plasterboard and paint it. However, sound will travel through the weakest entry point, so you would be obliged to cover the entire wall (top and bottom).

These are great ideas! I definitely like to build out the wall in some way. Are there any other thoughts on the finishing? Maybe a cool wall paper? HD has some wall panelling that is looking neat...

In order for the sound box to work, you need to have a porous surface (i.e. fabric) on your side. The sound waves enter and get bounced around the egg crate foam until they die. But you could use any kind of fabric (upholstery, drapery. sheeting, etc.).

I really like the slides on the wall . If you can add some batting and another layer of drywall this should give you a sound proof wall. i would then paint that wall red or


and get a Director chair ,