rigid fiberglass vs foam

[notbradsohner]

whats the difference? I am making an isolation booth, and want to deaden the sound, so there is no natural reverb, but what would drive me to spend less on 703 as opposed to auralex? i can afford stuido foam, but you guys make it sound like rigid fiberglass is better. is this true?

 

[SHEPPARDB.]

Why not use 2" 8lb. density rockwool?Build your iso booth
using the inside out wall method.Fill the cavities with rock-
wool and cover it with muslin.Makes for a completely dead
room w/o spending a fortune.

 

[Capt Dunsel]

whats the difference? I am making an isolation booth, and want to deaden the sound, so there is no natural reverb, but what would drive me to spend less on 703 as opposed to auralex? i can afford stuido foam, but you guys make it sound like rigid fiberglass is better. is this true?

From what I've gathered (after reading many of the posts here) is that fiberglass isn't necessarily better per se, just way cheaper for the same amount of absorbtion.

In my opinion, if you can find 703 fiberglass in your general vicinity, it's the cheaper way to go. If you have to have it brought in special for you, then it's a wash, since the shipping costs would eat up some of the savings, plus the labor and materials required to make a frame for the fiberglass, then cover it with cloth of some kind would eat up a lot more savings.

My $0.02

 

[notbradsohner]

please elaborate on your idea SHEPPARDB. I have no idea what you are talking about

 

[Ethan Winer]

Folks,

> From what I've gathered (after reading many of the posts here) is that fiberglass isn't necessarily better per se, just way cheaper for the same amount of absorbtion. <

No. For a given panel thickness rigid fiberglass is about twice as effective as acoustic foam. Or put more accurately, rigid fiberglass absorbs well to about an octave lower than an equivalent thickness of foam. Rigid fiberglass is also cheaper, though it must be covered with fabric for appearance and to keep the fibers from getting into the air if you brush against it.

--Ethan

 

[notbradsohner]

then 703 it is

thanks ethan

(read you site, very nice, but only a litte blurb about foam)

thanks again

 

[Capt Dunsel]

Re: Re: rigid fiberglass vs foam

Folks,

> From what I've gathered (after reading many of the posts here) is that fiberglass isn't necessarily better per se, just way cheaper for the same amount of absorbtion. <

No. For a given panel thickness rigid fiberglass is about twice as effective as acoustic foam. Or put more accurately, rigid fiberglass absorbs well to about an octave lower than an equivalent thickness of foam. Rigid fiberglass is also cheaper, though it must be covered with fabric for appearance and to keep the fibers from getting into the air if you brush against it.

--Ethan

Ah, I see. Fiberglass is cheaper and MORE effective than foam. Got it. Thank you sir!

The Dunce

 

[SHEPPARDB.]

please elaborate on your idea SHEPPARDB. I have no idea what you are talking about

Once you have the wood frame of your iso booth completed,apply
a layer(or 2)of sheetrock to the outside of the structure.This will
leave open cavities in the structures interior that can be filled with
rockwool bats.Once that is done cover the interior walls with muslin to keep the fibers from becoming airborn.
I'm not sure how the price of rigid panels compare to the prices of
rockwool(anyone have a price list?),but I do know that the rigid can often be hard to get w/o an HVAC certification.
Anyway,hope that helps.
Sheppard