Soundproofing my ceiling.

[Gempulse]

I live in an apartment in my parents basement. The living room in which they watch TV is right above my HT room, and their bedroom is two floors above my HT room. I usually have to keep my listening volumes at a respectable volume when they are home. Though, I would love to be able to listen to whatever I want as loud as I want without disturbing them.

I have a 3/8" thick drywall ceiling in my HT right now. I have been saving up money to completely deaden the sound in my room & keep it from going up to my parents area's.

I am going to be getting enough 5/8" thick drywall & Green Glue to add another layer onto my current ceiling.

How much do you think this would help my situation out?