Room/wall treatments for new basement?

Interesting;
http://cgi.audiogon.com/cgi-bin/cl.pl?accstwek&1065291017&2&3&4&

I am in the process right now of finishing my basement. The reason for doing the following is to keep the music from traveling through the floors and ductwork. Also would hope it has some acoustical benefits in the listening area.
I don't have an issue with walls because I used styrofoam building blocks as the frame for the poured concrete. I am taking a lot of time though with insulating the ceiling and around the duct work. After building a frame around duct work I put in 3-6 inches of insulation, depending upon the area available. I am then going to place 6 inches of insulation between the floor joists, being sure to overlap it with the insulation going up the sides of the duct work. The insulation will be flush with the bottom of the joists.
Before the drywall goes up the duct work and ceiling will be cover with soundboard (fiberboard). This should be a better solution than 2 layers of drywall. Also feel that the soundboard with isolate the drywall from the joists to possibly reduce resonance.
This may not be the best thing to do, but I felt it was a reasonable thing to try. Doing the work myself so I don't have to listen to a builder saying I'm crazy. Well, maybe I am, have to wait and see.
Good Luck

I would consult with the people at www.echobusters.com. The echo busters people supply materials to the professional trade not just to home audio. They will be happy to consult in your project. Give them a call

Good luck

Many of us have written extensive threads here and I would suggest doing a search. You will find a wealth of opinions.