How to design music room?

Unless you are prepared to do a lot of research I would suggest someone like Rives or Rives to give you advice. Stay away from the high end acoustic companies. They are a rip off. Do a search on the threads here and you will find a wealth of good advice. On the floor you should do a double subfloor with 1/2 inch or better cork in between the two layers of subfloor. You should also consider rubber strips or other separation methods between the joists and the first layer of subfloor.

Make sure that you play the music in your room on the first place:-)

Hueske-
primary goal is the best accoustics, secondary is noise isolation, and overall goal is listening nirvana
joeb

Steel door so your wife cant get at you......

Joeb,
If I had a chance to do whatever I want, I would build something like :

http://www.positive-feedback.com/Issue3/maroom.htm

Well, at least try to build room with "golden ratio” dimentions.