pneumatic isolation

Greetings. I've been lurking here for about a month. I plan on a build in 2007. But, my question is more one of theory. Has anyone experimented with systems using pneumatic isolation as opposed to the use of neoprene. I know the cost would be much greater as well as the installation but I was just curious because I read a scientific article on pneumatic isolation in laboratories for bench instrumentation. BTW, you guys rock. Lots of good info. I just finisted the 4th addition of the master handbook of acoustics. lots of great info there as well. Denny

I wouldn't think air would be that great - no damping to speak of, so probably similar problems as with neoprene/EPDM (needing extra damping in other forms in order to not cause ringing) - Air itself is pretty stiff; pressurising it would increase that stiffness, decreasing the decoupling. Think I'd stick with sylomer, or an isolated slab... Steve

Air works as the spring in an MSM ssytem. The advantage of air is when very low system resonant frequencies are required, it is an economically viable method. Andre

At first I thought you were going to ask about something totally different, and it reminded me of a question a friend asked me a while ago. He asked me if it would be possible to suck out all the air from between the walls in my studio, creating a vacuum. :D Well yeah, that would be great for sound isolation, if all your physical decoupling is perfect... but there's no way you could maintain a vacuum. I thought it was a fun idea though.