Well, sound proofing and treatment are different things. Sound proofing involves a LOT more, floating floors layers upon layers of sound proofing material ect. ect.
This stuff will deaden the sound, as it does absorb sound, but it's mainly there to catch reflection points. Your neighbors are probably bitching about the bass, which travels much further than highs and mids so maybe look into some bass traps for you and your neighbors and a few panels strictly for better mixdowns?
I think i paid $60 for the set i bought, i am building my own bass traps, much cheaper..
Here is a few pics of them hung.. And i loved the pattern to... The company who makes them took over another company that was shutting down or something, everyone who purchased from them is very pleased.. Don't mind my desk, i am currently building a custom desk..
Sorry man, i was a little confused there for a second lol but no i'm not treating anything above, i have some good carpet and padding on the floor so for a small home studio, there is no need for any treatment above. If i had hardwood floors, then yes i would certainly treat my ceiling or make a cloud..
I love it how people buy accoustic treatment then just stick them on the walls anywhere (not sayin thats what you've done) its the first reflection that people with small project studios need to be stopping.heres a little link with some very good info about installing accoustic treatment.