[azzzy]

Originally Posted by Bubbagump

See here: http://bobgolds.com/AbsorptionCoefficients.htm

Looks like at a 4" thickness, 3.5-4 pcf mineral wool is the sweet spot.

A great link. Thanks a lot.

Actually Roxul Safe seems to be performing the best at 4". But the table has no data for Roxul Rockboard 80 at 4". Besides I'm thinking of making my bass traps at least 6" thick, if not more. Any recommendations for the thicker absorbers?

Originally Posted by Bubbagump

I wouldn't bother as that is a side effect essentially. You want to focus on having usable surface area.

From what I understand this side effect is significant enough to affect testing data. I keep reading that you should expose as much of your absorber as possible. Why not go further and divide it into more pieces to create even more surface?

Originally Posted by Bubbagump

I would not consider that common at all. 16" is used for measurement purposes at times. Usually a 2-4" gap is a very good place to be to have excellent performance AND still be able to fit yourself and maybe a chair in the room.

I am not too concerned with space. I just want to know the optimal distance from the wall and then see if I can make it happen.

Originally Posted by Bubbagump

No. First, what you describe will not do what you are thinking it will. And even if it did, you want broad band absorbers, not tuned traps.

Can you please explain what it will do? How is it a tuned trap? I think (and I might be wrong, which is why I'm asking these questions) a layered trap would be more broadband than a single density one. By the way, I am more interested in absorbing the lows. I will have diffusors to take care of the mids and the highs.