Acoustic panel thickness

[JPM]

I have 4" 703 panels in wall corners and ceiling/wall corners. I now need to treat ceiling and walls. What thickness is best? I was thinking 3" for walls and 1.5" for ceiling (my ceilings are really low - 6 ' 6").

Also need to make some gobos for vocals and acoustic guitar primarily. Is 3" good for those? Too thick?

Thanks,

JPM

[Ethan Winer]

The thicker the better generally. I favor at least three inches thick for everything. For your ceiling you should go with two inches thick if at all possible.

--Ethan

[JPM]

Thanks. So for the ceiling, I read that it's best to have a couple inches of space. Hypothetically speaking, would it be better to have a thicker panel against the ceiling or a thinner one suspended if I had to choose because of my low ceilings. 4" total is a lot to loose.

[Glenn Kuras]

Originally Posted by JPM

Thanks. So for the ceiling, I read that it's best to have a couple inches of space. Hypothetically speaking, would it be better to have a thicker panel against the ceiling or a thinner one suspended if I had to choose because of my low ceilings. 4" total is a lot to loose.

Thicker panel is going to do better then a 2" panel with a 2" air gap.

Glenn

[AMIEL]

Originally Posted by myfipie

Thicker panel is going to do better then a 2" panel with a 2" air gap.

Glenn

Hi Glenn! what's is the situation of the gap between the wall and the panels?
why is not good just to place the panels against the walls?

should you fill up the gaps in the Corners? ..I mean the triangular space?
I saw GIK have a trinangular corner panel...for the corner..so there is not a gap...

[Glenn Kuras]

Originally Posted by AMIEL

Hi Glenn! what's is the situation of the gap between the wall and the panels?
why is not good just to place the panels against the walls?

should you fill up the gaps in the Corners? ..I mean the triangular space?
I saw GIK have a trinangular corner panel...for the corner..so there is not a gap...

This is off Ethan Winers acoustic page:

"The reason an absorbent material like fiberglass works better when spaced away from a surface is that sound waves passing through it have a greater velocity there. As a wave approaches a boundary, such as a wall, the velocity is reduced, and when it finally hits the boundary, the velocity is zero. Imagine a cue ball as it approaches the side rail on a pool table. The ball could be travelling 100 miles per hour, but at the exact point where it hits the rail it is not moving at all.

Likewise, fiberglass placed exactly at a rigid boundary does nothing because the air particles are not moving there. And since there's no velocity, the fiberglass has very little effect. As fiberglass is spaced further from the wall, the air particles passing through it have greater velocity. They are slowed down as they pass through the fiberglass, which converts the sound energy into heat therefore absorbing some of the sound."


As you can read the air gap will help, but if the whole area (like our Tri Trap) is used then it does work better because there is more mass thickness to absorb the sound. A 4" panel spaced off the wall 4" will do pretty well, but if you had 8" of just rigid fiberglass or mineral wool against the wall that would out perform the gapped 4" panel.
Now with everything I just said, I get the question all the time "Should I buy The GIK 244, the Monster bass trap or the Tri Trap". I always tell them the same thing which ever product you use you will need the same amount of each one (or close to it). 8 GIK 244s will work better then 4 Tri Traps or 4 Monsters in our room. But 8 of the Monsters or 8 Tri Traps will ROCK!!!!!!!! The best way to think of this is microphones have different qualities, but you would not go and buy a U87 if all you have to spend is $2000 total for all of your mics. You would only end up with ONE mic.
Glenn

[Cojo]

Originally Posted by myfipie

but if you had 8" of just rigid fiberglass or mineral wool against the wall that would out perform the gapped 4" panel.

Hi Glenn.

But if you space the 8" trap would it be even better!?

[Glenn Kuras]

Originally Posted by Cojo

Hi Glenn.

But if you space the 8" trap would it be even better!?

Well sure if you have 16 inches or so to give up.

Glenn

[George Necola]

PU or PVC (polyurethane, or polyvinylchlorid) foil does also help breaking standing waves.. works great at a backwall or something.

you can easily calculate this stuff.

leave a small airgap, because of humidity, so it can pass between the fibreglass and wall.



cheeers