sound proofing
 

apart from egg cartons, whats a cost effective way to sound proof a booth?

carpet backing, roll-out sponge, fiberglass insulation (don't wanna touch it or breath it in obviously), seen heavy velvet curtains, comforters, basically anything soft, and ideally, not flat. flat reflects sound too bluntly and widely, curves and lumps deflect and break the sound up.

soft absorbs.

i use mattress foam...