Sound proof

[swacholtz]

What is the most sound proofing material?

[YT2095]

it depends what you mean by sound "proofing"?

do you want sound not to be reflected for instance or stopped dead in a Vacuum like double glasing.

alot of the time it`s more important how the materials employed rather than the actual material, think of the exhaust muffler on a car, it`s mostly all metal construction

[insane_alien]

vacuum although it is hard to suspend the chamber, in which you want to carry out whatever you want to do in it, without some vibrations leaking in.