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Post by casa13 on Jun 23, 2016 2:25:19 GMT
I live in a cube an one of my walls is a massive mirror. So you could say my room is the worst possible although Iv put some foam around the room to help with the higher frequencies what's best for the lower frequencies?
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Post by rock on Jun 23, 2016 13:24:17 GMT
Hi, As you know a cube is just about the worst shape next to a sphere. Ethan has a room mode calculator but it is not for Macs so I found this on line calculator: amroc.andymel.eu/?l=8.2&w=8.1&h=8&ft=true&r60=0.6In the link above, I input dimensions for a room almost 8 feet cubed. I offset the dimensions slightly to show how the modes "pile up" at the same (almost the same) frequency and that's what's so bad about the cube. It will make your modal peaks and nulls that much higher and deeper. If you want to eliminate (you can actually only reduce) those modes you need lots of absorption at those frequencies especially the lower ones. I know, and you will read that Ethan has used resonant panel absorbers in the past, but now, I understand that he generally recommends porous absorbers for small rooms. I wonder if the small cubic room might be a candidate for the resonant panel? If porous is still the best approach, you need lots of 4 -6 inch thick panels, straddling all 12 corners and more spaced off the ceiling and walls. Cheers, Rock |
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Post by casa13 on Jun 24, 2016 22:01:11 GMT
So by porus traps you mean foam corner pieces instead of panel traps?
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Post by Hexspa on Jun 24, 2016 23:27:27 GMT
So by porus traps you mean foam corner pieces instead of panel traps? Think of porous as a greater term than form or panels. Meaning foam and panels are both porous. I'm inclined to prefer insulation such as OC 703, dense mineral wool or fluffy like R30 mostly because if you make it yourself it's a more flexible, if not more effective, and certainly cheaper option. |
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Post by casa13 on Jun 25, 2016 1:27:16 GMT
So ultimately would foam corner pieces be best or actual panels?
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Post by rock on Jun 25, 2016 1:28:22 GMT
Right, I was not clear but yeah, foam, fiberglass, mineral wool, cotton batts are all porous absorbers and generally absorb a wide band of frequencies, the thicker the lower and if un-faced with paper, foil or plastic extend to the upper audible frequencies. In contrast, resonant panel absorbers only cover about an octave or so and depend on the resonant frequency of the panel.
Yes, I agree, you can get better performance than sculpted foam from either Real Traps or homemade ones from OC703 or mineral.
Cheers,
Rock
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Post by rock on Jun 25, 2016 14:07:06 GMT
Once again casa, I did not answer your question: "So ultimately would foam corner pieces be best or actual panels?"
The foam corner pieces are usually too small (12" x 12" x 24 high" will have a diagonal face of only 17" across the corner) to be very effective. 2' x 4' x 4" thick rigid (dense) fiberglass or mineral wool panels straddling the corners are a better choice.
Ultimately it comes down to thickness and area of coverage. The greater the thickness, the lower the frequencies absorbed (spacing away from the wall or ceiling counts). The more area covered, the greater total absorption. You need both. Absorbers not at reflection points (in all 12 corners) should have foil, paper or plastic film facing the room for improved LF absorption.
Cheers,
Rock
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Post by Hexspa on Jun 26, 2016 0:51:31 GMT
You can probably compare acoustic foam to beer foam: a little is ok but it isn't the main solution.
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Post by rock on Jun 26, 2016 1:32:42 GMT
Ha Ha! But yeah, in general, the commercial "acoustic foam" is far inferior to Real Traps or their DIY counter parts.
Cheers,
Rock
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Post by casa13 on Jun 27, 2016 9:53:11 GMT
Cheers fellas
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