[JakeStone]

Thanks again for the additional comments on the subject.

Good stuff!!

Originally Posted by Standicz

of course that foil makes no difference, the sound just slips through. Even glass creates little reflection, it flexes and transfers the energy to kinetic. The same goes for drywall, which usually has rockwool beneath..so JakeStone probably does not need to treat the ceiling, unless I'm mistaken.

It really matters what the walls are made of and how thick they are. When the soundwave hits solid wall of brick, stone or concrete, it can't transfer into anything so it bounces off untill it's energy is depleted and it turns into heat completely. Higher frequencies bounce off more easily while low frequencies have more pressure and shake the whole house...it's like hitting the wall with a tenis ball vs a bulldozer.


As for absorbtion, the sound wave gets truly absorbed by a material thick 1/4 of the wave's lenght. That is the wave doesn't slip through if the whole height of it disappears in the material.

That means to trully absorb 27,4 foot long low E on a bass guitar, you would need 7 foot of rockwool!
440Hz A is still 27 inches..

So when treating a room, you are really going for ballance.

By the way carpet is great, much better than most other options!

also leave some space between the panel and the wall so the wave gets further absorbed when it bounces off the wall. That space should be as wide as the panel is. It kind of doubles the panel thickness.

Oh and early reflections are the root of most acoustic evil, treat the frist reflections first, just imagine where the waves hit right in front of you as they leave your instrument and those are the spots you have to address first..