Any advantage to floating a floor and not the walls

I have a room built already (live room). The walls were constructed well, but were just built on the concrete slab that existed. My questions is will I receive any benefit from building a floating floor and leave the walls as they are. Maybe do not attach the new floor to existing walls. I am trying to figure a way of isolating vibrations from the outside world without having to tear down the existing structure. I know I could build a whole new room within the room I have, but it seems to be overkill and twice the money. Any suggestions would be wonderful. Thank you

Not as simple a question as it seems like it should be - can you post a drawing of your present construction, and how everything interconnects? As much detail as you can give, specifically how framing, sheathing, etc, is fastened, and where - Steve

I will have to gather this info. Right in the middle of a time consuming project. I will post ASAP. Thanks for your responce.