I know that best material (nowadays ) is "mass loaded vinyl" but I searched a little for alternatives. I found locally Styrenebutadiene Rubber 3mm with mass of 4.5kg/m2. The Shore A (Durometer) hardness is 65, so I wonder is it suitable to replace MLV membrane. I checked some of the "popular" MLV products and found that hardness is approx. 70-85 shore. Does it really matter and if does, how it translates to the limp mass efficiency? Comments are welcome, cheers
