killing hard drive and pump noise DEAD. insulation
 

ive done a few experiments with trying to deaden the low frequency sounds of a baracuda IV and a pump... ive tried spongy type computer foam, polystyrene and some stuff which didnt work...

polystyrene does fairly well at decoupling vibration, but does really well at not letting sound pass through...

i plan to glue foam to my HDD waterblock, then glue polystyrene to that, and seal it up nicely. maybe ill make a polystyrene box lined with foam and just put the HDD/pump inside.
then if theres still noise coming from the enclosure, i reckon glueing foam to the polystyrene box, then putting another layer of polystyrene over that.

basically, the HDD/pump are watercooled, vibration decoupled with foam, then the noise is contained using polystyrene. silicone tubing will be used.

ive also got some camping mattress style foam to try out. its about 1cm thick, rubbery, very dense and you can squish it a bit.

any comments?

You're on the right track.

Step 1: block the noise.
Step 2: de-couple the noise.

you've done this before, no?

just did some experiments :)

i might be watercooling my DVDrom and CDRW aswell. gonna put them both vertical, using up 4 5.25" bays, i can then fit about 15mm of polystyrene above and below them, and on the sides and back (with some decoupling foam).
obviously its not ideal, and there wont be a perfect seal on the "lid" or cover that goes in front of the drives, but im sure they will be a lot quieter.

gonna play with this rubbery foam mattress type stuff aswell, might work better, and i can fit more of it in. it looks like it would decouple vibration better than polystyrene.

im thinking of maybe using some type of clamping mechanism to hold the cover on firmly, to hold the noise inside the enclosure, and then mod the CDrom drives, so that their drive tray motors cant run while its closed, and if they do try run a light flashes or something. :/

i have thought of "stealthing" the drives with the cover, but i dont think the seal will be good enough. CDROMs are loud.

ideas?

If it's any help, I was just going over silencing options earlier today:

http://store.yahoo.com/directron/noisestrips.html
http://store.yahoo.com/directron/grommet.html

(I *still* have no affiliation to Directron)

Seems like the right way to go.

dude, both of those solutions are really crap. conducted vibrations are only half the problem.

have you seen that hard drive silencer that guy on overclocksers.com made?

he put his hard drive in a foam lined box, with a waterblock on it... its the only way to go...

its pretty simple to do, just drill out the rivets for your hard drive cage.

Yeah, I was thinking about the rubber washer thing last night; it's only work if one used like, 8 of them (1 between the screw head and mounting plate, then 1 between the plate and the drive) and that assumes that there's a hole big enough.

I never bothered to look at the noisestrips; it seemed to expensive anyways.

Personally, I'm against wrapping things up like that; it's potential trouble for overheating, and/or reducing the life of the device. If you want to wrap something, wrap the whole box, and use baffle plates, to leave some ventilation.