so i live in an apartment and i want to setup a studio style room in my closet and if i throw some foam in there will it make it more soundproof for the outisde of the closet? i understand that vibrations from the studio monitors i have will still somewhat rattle the walls but my closet isnt to close to my neighbors…you think ill be okay if i really fill the closet with some foam or is this just a lost cause?
Foam dosnt soundproof at all really.
Air barrier and mass are the only things that are effective.
Professional sound proofing is usually done with mass - spring -mass.
Heavy walls - airtight cavity - heavy wall.
Bass is much harder to stop than high frequencies and can take a lot of mass.
You could try building some bass traps.
bass traps wont do anything to help sound proofing… they are only for controlling the sonic response of a room.
I’m a builder and regularly do refurbs which require sound proofing ie flats, and cinema rooms.
To properly sound proof you would need to do stud/ timber walls with clearance of two inch off existing walls filled with four inch dense sound insulation then covered in acoustic sound board and plastered, same for ceiling and any floors between you and your neighbour.
Believe me to actually soundproof a room properly is extremely costly I’d rather just keep the music at a moderate level which is better for producing anyway imo
Hope this helps 
[quote]phil johnston (24/08/2012)[hr]bass traps wont do anything to help sound proofing… they are only for controlling the sonic response of a room.[/quote]
Doh!
yea chris and phil are right when you’re talking sound proofing… you’re talking big bucks!!! that means you’re trying to get it to where your neighbor doesn’t hear anything your doing.
which = mega insulation
like what chris said just mix at a minimium level and get some accoustic treatment in the right spots and yes some bass traps in the corners if you can.
check out these vids
got to youtube and type in “francis buckley studio rescue” he is a grammy award winning audio engineer. 