Registered: 04/20/04
Posts: 7
Loc: Northern Virginia
Offline
I want to buy some OC 70x to make some general purpose acoustic treatments. My local dealer only sells them buy the case. What would be better to buy for bass absorbtion and reflection?
I'm thinking 2" 705 FRK.
Here's another idea if I have the $$$. 1 case of 2" 705 FRK and 1 case 1" 703. Then make a panel that has the paper in the middle with the 705 toward the wall and the 703 towards the room. Would that be an improvement over just using 705?
Registered: 06/12/00
Posts: 5375
Loc: New Milford, CT, USA
Offline
BG,
My gut feeling is the 703 with FRK will outperform 705 without FRK. As for a sandwich with the FRK in the middle, I don't know that either but my guess is it will not be as good as having the FRK on one side only.
--Ethan
_________________________ www.realtraps.com The acoustic treatment experts
Am I correct in interpreting these numbers to mean that the non-backed versions have better absorption at higher frequencies and the backed are better at lower frequencies?
I haven't finished building my room yet, but it will by around 11'x16'. I will be finishing the ceiling because isolation/sound proofing is important to me. Since all walls will be drywall, I know I will need some absorption in higher frequencies as well as the lower ones for bass response.
When I make the acoustic panels, should the backing face the wall or the room? It seems like having the backing face the room would not absorb highs very well, buy might handle bass better. Having the backing toward the wall would tame high frequencies. Is this correct, or does it not really matter?
Finally, because of WAF, I'm concerned about having 2' panels spanning the corners in the room. Would it be better to have 1' panels span the corners or 1' panels on each wall of the corner - sort of like what you did in the video.
Registered: 03/13/04
Posts: 125
Loc: Hamilton, ON Canada
Offline
Quote:
Am I correct in interpreting these numbers to mean that the non-backed versions have better absorption at higher frequencies and the backed are better at lower frequencies?
Yes you are.
Have a look at the data in the "70x Absorption" thread also. Note that 703, 705, at 3" are the same for practical purposes.
Quote:
Would it be better to have 1' panels span the corners or 1' panels on each wall of the corner - sort of like what you did in the video.
1' panels spanning the corner will give better low end absorption.
but my guess is it will not be as good as having the FRK on one side only.
