Vacuum Room

is it possibe and/or normal to soundproof a room by creating a vacuum in between the inner and out walls of a room within a room scenario? I was thinking that if i could set up even a partial vacuum then surely would i not stop a big lot of the sound from entering the room? can somebody tell me the upsides/downsides to this line of thinking and if there are any suggestions as to how i might go about this it would be much appreciated.

Can you breath in a vacuum? Would you have to decompress when you leave that space? Would exterior noises make it sound like your on a submarine? Being in an anechoic chamber makes me 'feel' like i'm in a vacuum.

an isolated vacuum. the inside room is airtight, the outside room is airtight and the vacuum is in between.

And how do you propose to keep that air at a vacuum without any rigid coupling of the inner and outter walls (remember structure borne transmission)? Enter magnetic levitation, and dedicated air supply hoses.... I don't even think NASA could afford a room like this. K