Re: Sound Proofing
No, but I have looked into it. My understanding is that there are several options incorporating sound reduction methods and materials.
One very effective way is to attach "U" shaped battens horizontally and 'hang' soundproof (heavy cement based) plasterboard from these battens, leaving a small gap all round. This gap is filled with sound absorbing mastic. The soundproof boards can then be covered with a normal gypsum plasterboard.
Problem is that this is expensive and takes a couple of inches from your room, but is supposed to cut out 80-90% of transmitted noise.
There are 'slimmer' options available such acoustic panelling in conjunction with plasterboard, but I don't think it's as simple as stuffing a cavity with foam.
If there is a window in the wall , then triple glazing would help a lot too.