Acoustic Material

[Ciscokid]

I have searched and searched for OC 703 /705 in my area to no avail.I did however find a mineral fiber called Thermafiber Safing. Has anyone ever heard of this? I can not find any acoustical information on this product. It comes in 2x4 sheets 3inches thick.


I am finally ready to build some bass traps for my room.I was just wondering if anyone is familar with this product.Thanks.

[bpape]

Is Thermafiber the brand name? Not familiar with it. If you can find out the density, you can probably extrapolate an approximate performance level. Just understand that any mineral fiber with similar density to 703 or 705 isn't going to be very rigid.

Did you also try to look for the comparable Johns Manville or Knauff 3lb/cu ft rigid fiberglass boards?

Bryan

[abhi]

I guess Accurate Firestop (Javier) @ Hayward carries Roxul boards at a very reasonable price. I read it in some forum. I contacted him once but didn't get a chance to go and take a look at the boards.

[abhi]

bpape wrote:

Is Thermafiber the brand name? Not familiar with it. If you can find out the density, you can probably extrapolate an approximate performance level. Just understand that any mineral fiber with similar density to 703 or 705 isn't going to be very rigid.

Did you also try to look for the comparable Johns Manville or Knauff 3lb/cu ft rigid fiberglass boards?

Bryan

Here is the pdf for Safing:
http://www.thermafiber.com/pdfs/TF612.pdf

It doesn't talk about acoustic properties though.

[bpape]

No - and it doesn't give me density either.

This is the most I could find on Thermafiber.

Thermofiber 1" 4pcf 0.06 0.24 0.58 0.81 0.85 0.90
Thermofiber 1" 6pcf 0.07 0.24 0.62 0.87 0.91 0.91
Thermofiber 1" 8pcf 0.10 0.37 0.82 0.97 0.91 0.89
Thermofiber 1" 12pcf 0.09 0.31 0.77 0.96 0.99 0.94
Thermofiber 2" 4pcf 0.24 0.68 1.08 0.99 0.92 0.92
Thermofiber 2" 6pcf 0.32 0.81 1.09 1.02 0.94 0.94
Thermofiber 2" 8pcf 0.35 0.84 1.04 0.96 0.93 0.93
Thermofiber 2" 12pcf 0.40 0.79 0.94 0.94 0.87 0.87
Thermofiber 4" 2.5pcf 0.63 1.15 1.15 1.05 1.05 0.94
Thermofiber 4" 4pcf 0.77 1.14 1.15 1.04 1.04 0.94
Thermofiber 4" 6pcf 0.84 1.11 1.11 1.05 1.05 0.93

Bryan

[Ciscokid]

Thanks for the information. I did come across this PDF for thermafiber.The only issue is I am not sure what product this is for since they make several different products. They have the Safing which I can get. They also have an sound attenuation blanket and a curtain wall insulation. I would think they are probably pretty similar.

I think I might check into some of the other products you guys have discussed and see if they are available in my area.

[basementjack]

2 things:

1) rigid insulation is typically available from a few types of places...
- furnace supply shops sell it - it's used to make ductwork in some cases...
- insulation supply shops sell it - look in the yello pages for insulation supply or insulation distributor.

2) don't get hung up on which exact panel to purchase and use. while there are some differences, they should be taken with perspective
- if you want guaranteed, documented performance, buy a GIK panel or a realtrap -both of those companies have done thier homework... yet even with both of those companies fine product - both will openly tell you - it takes ALOT of panels to make a room perfect.
- so take that into consideration - it's not like you if you research and find the perfect 703, that one panel will fix your problems - You'll do far better off with multiple panels of just about anything - if the specs are furnished try for something close to 6 pound per cubic foot, but if it's 3lb/ft don't sweat it.
and buy as thick as you can tolerate, and lastly, plan for them to be away from the walls - even if it's only a little bit - some of the biggest bang for your buck is a piece put diagonally in the corners.

Hope that helps - and please have a look at the site sponsors (GIK acoustics is one of them- and they practically give those panels away!)

- Jack

[Josuah]

You should be able to find semi-rigid fiberglass locally. Look in the phone book under _commercial_ insulation companies. Not residential.

[bpape]

You've gotten some good advice. I will clarify one thing. The density of the material to be used for optimal performance in a given application depends on a few different things. The biggest of those things is how thick you'll be making them.

As an example, 705 is basically double the price of 703 (6lb vs 3lb). So, given a choice, I'd rather have a 6" thic absorber from 703 than a 4" thick absorber from 705. The 6" 703 will perform better and 25% less. Now, by the time you get to that stage, you can (with the same amount of 703 for the same height and size of absorber, you can build a solid chunk that will do MUCH better below 80Hz than 6" straddling. Why? Because at it's deepest point, it's a solid 12" thick.

Another example is when making reflection point panels. If your speakers are far away from the side walls, then your angles of incidence for the reflections are relatively steep. However, if you're close to the side walls, there are some really shallow ones. 6lb material has a tendency to allow high frequencies to skip off at shallow angles of attack - 3lb not nearly so much.

It would be great if there was a single best product for everything - unfortunately there isn't. The reason most people use 703 is because it's a good all around product that can be used for pretty much anything and the cost is at least somewhat reasonable.

I appreciate the kind words about our product. I'm more than happy though to help with DIY projects also.

Bryan