http://www.mec.ca/Products/product_listing.jsp?FOLDER%3C%3Efolder_id=677965&bmUID=1065992271025

Having bought some of these sleeping pads from Mountain Equipment Co-op (a Canadian company that sells outdoor type clothing and equipment which ships internationally by the way) that they might be really good for sound baffling?

I'm wondering if anybody has tried something like this! The thing about this store is that it's a co-op and has really low mark-up so it might be an awesome alternative budget-wise.

I don't know of any specific reason why cut up sleeping pads wouldn't work, but I've never heard of them being used. The only thing that might be an issue is that the more commonly used carpet pad foam is an 'open cell' type foam, while most of the sleeping pads that I've seen are a 'closed cell' type. I don't know what the difference in sound absorbtion might be.

The prices on the website you pointed at seem reasonable for sleeping pads (as compared to what they cost here in the Boston, MA, USA area) but I suspect that you could get carpet padding for much less.

Gooserider

Yeah postul8or, the sleeping pads you're loking at are among the cadillacs of non-self-inflating pads. For one just to try I'd suggest heading to your local Walmart and buying a $7 one there. (Do you have walmarts in Canada?)

For the truly cheap at heart (otherwise known as an ecological, recyling environmentalist)... I got some scraps of brand new high density carpet underlay at some big carpet outlet for zilch. Works ok. Better than the closed cell sleeping pad foam.

Yep that's actually what I did today, picked up a 3/8" sleeping pad at Wal-mart for something like $10 (Cdn currency, pretty close to the $7 you mentioned).

I'll experiment with it and see how I like it. I live in a new development neighborhood so I figure it will be easy to find some left over pieces of underlay in the recycle bins so I'll try those out too.

If I have any kind of results to post I will do so, but I don't have any real objective sound measuring equipment. Unless somebody can explain how I can hook up a microphone at a specific distance and use some software for it I think it's up to my ears...

What is the difference between open cell and closed cell? Is it related to how the air pockets in the foam are formed or something?

basically, yes.

Open cell foam has air pockets that connect to each other, and to the outside. Sponges are open cell, so are your lungs.

With a closed cell foam each of the little air pockets are sealed, and independant from each other. (They make sleeping pads from closed cell so they won't soak up water. Nothing's worse than finding out that your tent leaks when you're lying on a giant sponge)

The theory is that open cell foam will allow the sound waves to penetrate further in, so they'll be absorbed rather than raidiated back out. With a closed cell foam the sound waves may just bounce off the outside surface.

Interesting, I have done the top, 1 side and floor of my case with this closed cell foam and I'm fairly impressed with the results.

The loudness of the power supply fan at the back of the case is more noticable. On hard drive reads the sound comes through the back, and the sides are more of a low frequency rumble now. The main thing I will be interested to see is the damping effect on the hard drive hum when I do work on the front part of the case.

The PSU fan is an obvious replacement to be made next weekend. I've got another post going about which fan to purchase, but if you have a recommendation please let me know.

Thanks.

You've discovered one of the great laws of silencing....

As one part getgs quieter the others seem to get louder.

The PSU fan swap is a fairly easy mod to make. I'd suggest a Panaflo 80mm L1A as the replacement. (the L1A refers to last three digits of its model number, sorta a short-hand for the Low speed model. Don't buy one that ends in H1A (high speed) or U1A (ultra))

Do some browsing through the PSU forum...there's lots of discussions there about fan swaps.

I actually replaced a case fan on my 486 box, actually I had a P166 in the case at the time. The only sort of "shady" thing that I did was, clip the wires to the original fan, put the new fan on by twisting the wires and melting some of this rubber stuff that shrinks when you heat it.

I would think it would be cleaner to get rid of the wires at the source instead of clipping them. I can't recall why I did it, obviously saved me from digging up a soldering iron or something.

From the noise specs at the store I deal with it seems like some of the competitors beat the Panaflo. Not like it's a huge deal, I tend to wonder if I can hear thd difference between 24 and 26 dB for instance.

cool, so is that cheap stuff at walmart a better deal than buying that akasa pax.mate stuff? i was thinking about that stuff and perhaps putting a panaflo l1a into my antec powersupply that came with the sonata.

It is making a difference for sure, but I don't have a frame of reference to compare it with anything else so it's hard to say if it's the way to go.

I think you will find even if you go to the Home Depot, RONA etc. that you can get plain old carpet underlay (also called rebond - try to get 10 lb weight if possible, 8 is all RONA had when I went there) and it will be about the same cost as the sleeping pad.

Most of the gurus in here are saying the "open cell" nature of the rebond makes it a better bet for sound baffling. Maybe in time I'll be able to confirm or deny this hypothesis through experimentation.

My new theory is that focusing on quiet fans (and if feasible replacing fans with heat sinks) is a must because either way you must have an air intake and an air outtake which means you have pretty much 2 big holes in your case for sound to travel out of. I would say focus on this area first, then get pick about the foam material for your case.