John Sayers' Recording Studio Design Forum Archive

Hi

A friend to me wants to build absorbers to his hifi-room but doesnt want to use mineral fiber cause of environmental and health reasons. What about using linen fiber instead?

http://media4.bauhaus.se/media/catalog/ ... 05517A.jpg

Would it be as good as using mineral fibre?

Please respect that i dont want a discussion of the pros and cons with mineral fibre or that the mineral fibre doesnt affect your health, etc.


This is what the company says:

Thickness Frequency
>
> 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz
>
> 50mm 0,20 0,45 0,70 0,80 0,90 0,95
>
> 100mm 0,65 0,75 0,75 0,85 0,90 0,95
>
> 150mm 0,80 0,90 0,90 0,90 0,90 1,00

>
> For 50mm thickness:
> Rated sound absorption degree, single value over the entire frequency range (αw): 0,70.
> Sound absorption class C with overall system-depth of 0mm (directly mounted on the room surface, without air-gap or other layers).
>
> For 100mm thickness:
> Rated sound absorption degree, single value over the entire frequency range (αw): 0,80.
> Sound absorption class B with overall system-depth of 0mm (directly mounted on the room surface, without air-gap or other layers).
>
> For 150mm thickness:
> Rated sound absorption degree, single value over the entire frequency range (αw): 0,90.
> Sound absorption class A with overall system-depth of 0mm (directly mounted on the room surface, without air-gap or other layers).

Thank you for your help, much apriciated.

A friend to me wants to build absorbers to his hifi-room but doesnt want to use mineral fiber cause of environmental and health reasons.

Your friend seems to be misinformed about the issues:

https://www.gearslutz.com/board/bass-tr ... eview.html

He also seems to be misinformed about how acoustic treatment panels are built. If he is concerned about how one of the components of an acoustic treatment panel might affect his health, then he should be far more concerned about the cement powder that was used to pour the foundations of his building... but of course that powder is now harmless, since it has cured properly, and is no longer a threat. He should also be far more concerned about the wood fibers in the wooden parts of his building... except that those too are no longer a threat, since they were presumably properly incorporated into the structure. Ditto for the hugely dangerous chemicals that were used in making the paint on his walls.... except that those are also no longer a danger at all, since they were correctly combined and applied, and the paint is now properly dry.

None of those building materials are a danger any more, because they were correctly used in the building process. The same applies to mineral wool and fiberglass insulation: By themselves, in their raw state, I'd certainly agree that they are not something that you'd want to have uncovered on your listening room walls or ceiling! But by the time they have been properly incorporated into the acoustic treatment devices that are used in thousands of studios and listening rooms all around the world, the danger it is gone. They are no more dangerous than the cured concrete in his foundations, or the dry paint on his walls. Dangerous products are used all the time throughout construction, but they are rendered not dangerous by being correctly used and installed.

Would it be as good as using mineral fibre?

No. Compare the figures you show for those linen panels, against those for products such as Roxul HT, or OC-703. The latter is is pretty much the best acoustic porous absorber you can find.

For example, 100mm of your product has a coefficient of absorption of only 0.65 at 125 Hz but the same thickness of OC-703 is rated at 0.84. At 250 Hz, your product shows 0.75, while OC-703 is an amazing 1.24. Enormously better! You'd need two to three times as much of that linen product to get the same effect, thus creating a large fire hazard (linen is flammable, fiberglass is not) and taking up two or three times as much space in the room. Does your friend really want panels 30cm thick poking out into his room?

i dont want a discussion of the pros and cons with mineral fibre or that the mineral fibre doesnt affect your health, etc.

Why not? Why don't you want to hear the truth about mineral wool when correctly used in acoustic panels?

You make an unsupported statement suggesting that mineral wool DOES seriously affect health in studios, then you say that you don't want to hear anything about why your statement is misleading?

Why?

This forum is for discussion of all aspects of studio building, including possible health hazards. You brought up the subject, so I see no reason why the discussion should only be limited to your claims, with no possibility of hearing the truth.

Also, if you don't want to hear about the pros and cons of mineral fiber porous absorbers compared to linen fiber porous absorbers, then whey did you ask a question about the pros and cons of mineral fiber porous absorbers compared to linen fiber porous absorbers? The truth is that the linen does not perform acoustically anywhere near as well as mineral wool or fiberglass, so how am I supposed to tell you that (and why did you even ask!) if you don't want to hear it?

What about using linen fiber instead?

Your link leads to a photo of what appears to be some type of porous panel, but there is no acoustic or material data information there: just a photo. It is impossible to tell what that product might do in a studio, or what other characteristics it has, based on a photo. Do you have a link to the actual product specifications?


- Stuart -