i've been involved in the music business for some time (not in the soundproofing business but recording). I've seen many types of soundproofing a solutions. Here are some. 1. Layering insulation between peg boards so the holes are staggered like brick work. don't compress the insulation too much. 2-3 layers are ideal. though you need to cover 'cause of the insulation. any fabric should do. 2. same method as above but filling it with foam. i have also seen news paper and such used as a filler. 3. you can actually buy sound board from local lumber shops/yards. 4. making baffles/barriers and placing them to direct sound will work too. they'll need to be around 6" thick with peg board staggered inside to trap sound. that's how staggered peg board works. sound travels into one hole has to move around to find another etc. thus loosing energy and stopping. the more peg board used the more it'll trap.