Carpet and Vinyl, a good combo? (with pic)

Bobendren · Post by **Bobendren** » Sat Jul 01, 2006 2:37 am

Hi everyone, I have this stuff lying around:

That's some carpet, thin floor vinyl and thick floor vinyl.

Idealy i would like to glue some black foam on top of the thick vinyl, as i have a side window in my case and would like it to match the rest of the mod (case painted black).

I have some grey foam (the type you get with motherboards, but thicker) which i presume is open cell as i can breathe through it. Is open cell foam any good for this application or will only closed cell foam have any affect? Is the vinyl even necessary?

I don't really want to use the carpet unless i get a black dye for it...too much effort i think.

Please, any advice or opinions would be greatly a appreciated.

Bob

McBanjo · Post by **McBanjo** » Sat Jul 01, 2006 3:21 am

I assume you speak about damper the computer even if you doesn't say so

Vinyl is used to damper any vibrations in the case, basicly by doing it heavier. It suppose to work excellent.

I wouldn't use carpet, no mather colour. I think the risk for static electricity would be way to high. Might fry your hole computer.

Open cells are good, closed cells then the sound basicly just bounce on the surface rather than being absorbed.
The foam you have should most likely be rather good for absorbing.

A base rule is: the thicker the bether

Bobendren · Post by **Bobendren** » Sat Jul 01, 2006 8:39 am

McBanjo wrote:I assume you speak about damper the computer even if you doesn't say so

Yip, sorry i suppose i should have stated that somewhere.

McBanjo wrote:Vinyl is used to damper any vibrations in the case, basicly by doing it heavier. It suppose to work excellent.

Does the vinyl do anything for noise blocking or does it just absorb vibration?

McBanjo wrote: Open cells are good, closed cells then the sound basicly just bounce on the surface rather than being absorbed.
The foam you have should most likely be rather good for absorbing.

Are you 100% sure about that? Because i definately remember someone on these forums saying that open cell foam is a complete waste of time. Anybody know?

McBanjo · Post by **McBanjo** » Sat Jul 01, 2006 9:32 am

Does the vinyl do anything for noise blocking or does it just absorb vibration?

Not more than anything else I think, it's mainly for vibrations.

Are you 100% sure about that? Because i definately remember someone on these forums saying that open cell foam is a complete waste of time. Anybody know?

No I'm not since I'm not an engineer developing the stuff

But everything I've seen has been with open cells. You WANT the sound to enter the material then basicly bounses around until it dies. Sound dampering on the other hand is closed cells. Big difference between sound absorbing and sound dampering.
Since you need airflow in a computer you want sound absorbing. Dampering is more for a closed box like a room.

I did some research on this a little while agoe and this is how I understand it. Might be wrong ofcourse

Bobendren · Post by **Bobendren** » Sat Jul 01, 2006 12:13 pm

I found mutemat's website very informative: http://www.mutemat.co.uk/information.php

It seems what you mentioned is correct

. Open cell is the way to go, the higher the density the better.

From what i've read a dense and heavy vinyl layer acts as a noise blocker as well as absorbing vibration from the case and reducing resonance.

Bobendren · Post by **Bobendren** » Sun Jul 02, 2006 1:36 pm

It seems the open cell foam i have is actually semi-open cell foam. <gasp>

I have another piece of foam which is the same density and thickness as the semi-open cell foam but is much easier to breathe through. So i'm guessing the other piece is actually open cell foam and the original piece is semi-open cell.

It also seems obvious that the semi-open cell foam is a better choice for reducing noise. I tested this by simply placing the foam infront of stuff that makes noise, one being my router that makes a whining sound.

Also i see AcoustiPack uses semi-open cell foam. I'm going to try find some that is designed with the same shape they use. I assume they know what they're doing.

Or what about fibre glass? And I see mineral wool is a good alternative to fiber glass. Both are supposed to be better than foam right?

I've been browsing spcr on the subject for the last few hours and now i'm really confused. Please if someone could just verify what i've said here and/or correct me.

Thanks

Gorsnak · Post by **Gorsnak** » Sun Jul 02, 2006 4:08 pm

Yes, both high density rigid fibreglass and mineral wool are superior for sound absorption to foam. Any worthwhile sound absorption is likely to take up more space than you have available inside a standard computer case, though. Especially if you're serious about not giving up the case window. The inside of that side of the case is one of the few places you can fit significant absorbing material.

Bobendren · Post by **Bobendren** » Mon Jul 03, 2006 7:41 am

Well, it's for aesthetic purposes as well

I'll check whether fibre glass is a viable option.

As for the side window...what about using two (or several) peices of acrylic and leaving a small gap of air inbetween? Acylic is supposed to be a good sound reflector right?

Gorsnak · Post by **Gorsnak** » Mon Jul 03, 2006 10:09 am

Most likely you'd gain more from a small fibreglass panel placed behind the computer (see the third pic from the top here) to absorb the sound coming out the back than you would from the small amount of fibreglass you might find room for inside. You might try to use the vinyl just to increase the mass of the walls of your computer so that less sound passes directly through them, meaning it will be more directed through the ventilation openings. Stick some foam around the intake holes, and an absorbing panel behind the exhaust fans or something. With that window you're extremely unlikely to get enough absorbing material inside the case to make a noticeable difference. And yeah, acrylic will reflect most sound fairly well. Not so good with low frequencies, but your computer doesn't generate much on the low end in the first place.