Tuned Absorber Material Question

Two questions. Are there any issues with using mlv for the membrane (front) of a tuned bass trap? If so, can I glue two pieces together to form a higher density membrane ?

bluesbaz wrote:

Are there any issues with using mlv for the membrane (front) of a tuned bass trap?

That's what RPG uses for the Modex Corner bass traps.

can I glue two pieces together to form a higher density membrane ?

It's not the density but rather than total weight of the membrane. --Ethan

I see, well can i glue two or more pieces together to increase the weight of the membrane.

Gluing two pieces together will increase the total mass, but it will change the stiffness. the way I understand it, MLV works in this application because it is limp mass. If you glue two pieces together, it won't be limp any more. Or rather, it will be much less limp. It will be more rigid, stiffer, and will therefore have different acoustic properties. I'm not saying that those properties will be bad: they will just be different. It probably won't work the way you expect it to work, and you'll be entirely on your own as far as getting any technical specs on those acoustic properties. I'm not aware of much independently published acoustic data on MLV anyway, and certainly nothing at all on the properties of "two MLV sheets glued together"! Why do you need to increase the mass? What effect do you predict that will have? - Stuart -