Old Foam Mattresses.... room treatment value ?

Wolffman · 10-17-2009, 01:14 AM

I have 3 old single bed mattresses, 1 is 6" ( 150mm ) thick & the other 2 are 5" ( 125mm ) thick, are they of any worth as room treatment or should i just dump them

I'm guessing they will have an effect on some freq's but which ones i wouldn't know ? and i don't want to make the space worse than it is now by affecting the wrong freq's, ( is it possible to actually mess things up with the wrong treatment ? )

Currently i have zero room treatment, but my space is fairly big about 20x20" ( 6m x 6m ) and i have large doors which open directly to outside and i usually have these open when mixing.

I'm thinking of placing 2 of them on the wall directly behind my monitors, is this a good idea ? and maybe rolling the other up length wise and putting it in the corner to my left which is about 8" away to make a bass trap of sorts.

Your thoughts ?

Cheers

nicholas · 10-17-2009, 01:54 AM

Well you could try them out and see how it goes, but I suspect you'll be somewhat underwhelmed at the results ... that sort of stuff is better for sound-proofing than acoustic treatment. At least it means your neighbours won't have to hear your drums.

Good luck though.

JosMuysers · 10-17-2009, 04:34 AM

I would stick both of them in the corners for bass trapping and use something thinner between the monitors

dub3000 · 10-17-2009, 05:07 AM

might work but more likely will just muffle treble reflections while allowing bass to bounce around. this will just make your room boxier, if anything. do some before/after measurements using roomeqwizard (google it, it's free and great) and see if it's an improvement. really depends on how dense they are.

JHughes · 10-17-2009, 06:54 AM

It won't work well. Acoustic foam is open cell, and mattresses are closed cell IIRC.

Tedwood · 10-17-2009, 07:33 AM

I'm with Dub, foam will kill HF reflections only, but also don't discount them without trying them in different situations.

You have to try it out, but while you are at it see if you can find anything of greater density that you can put in corners for bass trapping as well.

Coerce · 10-17-2009, 08:57 AM

The only thing they will do is stop high end reflections. The only way to stop bass is from mass.

John Lundsten · 10-17-2009, 10:06 AM

Quote:

Originally Posted by Coerce

The only thing they will do is stop high end reflections. The only way to stop bass is from mass.

There seems to be some mixing up of Acoustic isolation (IE stopping sound getting in/out of a room - for which mass is good) & Acoustic treatment (lessening reflections)

Now a bit of foam is going to do dam all re isolation.

To lessening reflections, yes open cell will work better than mattress foam.

The way absorbtion works is that as sound waves force their way through a porus material {both going in then having hit a wall back out again} some sound energy will be converted into small amounts of heat.

The faster the sound wave is going the more friction therefore absorption there will be. A "plain wave" bouncing off a wall gets to it's max speed at a quarter wavelength. So if you want to absorb 200Hz say [which has a wavelength of approx 1.7m, & a 1/4 of that is 425 mm (or about 17inches)then place your mattress there and you will absorb maximally at 200Hz, 400, 600Hz etc etc upward quite well & and all the other freq will get absorbed to varying degrees too.

But stick it to the wall and it will only start to absorb at > about 1kHz.

Wolffman · 10-17-2009, 06:09 PM

Hmmmm.... guess I should just wait untill I get some Rockwool or accoustic rated fibreglass and do the job right

I just didn't want to toss them out if they had some potential use.

My room isn't too bad as it is strangely enough, I guess the big open doors help.

Thanks for your input fellas, much appreciated.

Cheers

strunkdts · 10-17-2009, 07:48 PM

Quote:

Originally Posted by dub3000

might work but more likely will just muffle treble reflections while allowing bass to bounce around. this will just make your room boxier, if anything. do some before/after measurements using roomeqwizard (google it, it's free and great) and see if it's an improvement. really depends on how dense they are.

registering for that service (roomeqwizard) is a long and stoopid process!

d. gauss · 10-17-2009, 08:10 PM

hmmm. music, extra mattresses lying around. i must be getting old, but soundproofing would be fairly low, to not even on the charts, on my list of best ways to use mattresses in a sex, drugs n rock n roll world.

dub3000 · 10-17-2009, 08:22 PM

Quote:

Originally Posted by strunkdts

registering for that service (roomeqwizard) is a long and stoopid process!

but it doesn't cost anything, and it's better than a lot of really expensive commercial software! it's worth it, really.

strunkdts · 10-17-2009, 08:53 PM

Quote:

Originally Posted by dub3000

but it doesn't cost anything, and it's better than a lot of really expensive commercial software! it's worth it, really.

it is,yeah, but isnt that registration like nothing else!?