Big, Quiet Fans.....

[KingJackal]

...are ( so far as I can see ) impossible to get.

I'm looking in the 150-180mm range, and the QUIETEST I can find are ONLY 50 something dB!! :eek: :eek:

Even if I get a 24V fan, and run it at 12V ( the quietest fan so far is a 24V 55dB 204cfm beast that can run on 12-28V ), it's still likely to be pretty d@mn noisy :(.

I suppose I COULD run a battery of 92mm's or 120mm's, but.....
*sigh*

Any bright ideas?

[I.R]

Well teh JayCar 150mm jobbie is 53db @ 3400RMP and that does 230CFM (Cat. YX-2520)..... it bloody expensive though $105 for 1, $94 each for 4+, and $83.95 each for 10+.... but then you already new that :p

[Binky Stunt Cat]

you could use 4 80mm Vantec Stealths...

[_N_]

what about those fans that are used in summer to cool a room down, run on 230VAC, or out of fan heaters with the heating unit busted?

[ktulu]

go for a bank of 92mm Panaflows (get them off magpie for $6 ea, mine are too expensive). They are quite quiet considering the amount of air they move... and you could always run them at 7V.

[Volodkovich]

go to a car wrecker and look arounf for some radiator fans of around the right size. Run them off 7 volts..Most of them only draw around an amp. Dunno if they'll be to big for you. The other good thing about this is that they are cheap. None of this $100 bullcrap.

[KingJackal]

The problem is:

- Those big Jaycar fans are 53dB. Even run at a lower Voltage ( as low as they start ), they'll still be too noisy.
- Panaflow's are noisy. I've got a similar setup ATM. They push lots of air, but are noisy. They DO make quiet models, but nobody seems to sell those models ( or get them, or anything - it seems the only spec people look at is cfm ).
- Vantec stealth's are too expensive and large numbers.
- Room fans are too noisy.
- I would have thought car fans would be insanely loud. Sure you don't here them when you're driving, but try listening to mp3's with your head 40cm away from one....

Thing is, most fans ( or groups of fans ) up at the 170-180mm ish region push plenty of air ( 200+ cfm ), but are waaaaaaaay too noisy ( 50+ dB ). I don't mind 80-100cfm total, but want LESS THAN 30dB, cos my current fans are up to 32dB, and are way too loud!! I would prefer 20-25dB fans. And all manufacturer's make these models.... just nobody seems to bring them into the country.

To show you what I mean, have a look here:
http://www.sunon.com.tw/product/traditional/t9225.htm

See? Sunon make a 120mm 12V fan that registers only 28dB. But the Sunon's you'll see in stores are normally the 33 or 34.5dB varieties. The same applies for Panaflow's.

I suppose in the end I'll probably wind up buying a battery of Panaflow's ( quietER models ), and running them all at a lower voltage. It's just annoying that large fans are only made with insanely high noise levels ( 53dB is actually too loud to be reccomended for use in an office according to OSH, last time I checked ).

[Binky Stunt Cat]

how much CFM are you looking for anyway?

[KingJackal]

Originally posted by KingJackal
I don't mind 80-100cfm total, but want LESS THAN 30dB, cos.....

;)

[Binky Stunt Cat]

oh, missed that....
*smacks forehead*
then an array of 4 80mm stealths would work, 27CFM per fan,but they're about $20 each i think.

but i tell ya, at 21dB each they are bloody quiet.

[Volodkovich]

hmm, i would have thought if u use a jones chopper in series with the fan you should be able to get it spinning slow enough as to not make to much noise, but still pump alot of air. *shrugs shoulders*

[KingJackal]

Originally posted by Binky Stunt Cat
oh, missed that....
*smacks forehead*
then an array of 4 80mm stealths would work, 27CFM per fan,but they're about $20 each i think.

but i tell ya, at 21dB each they are bloody quiet.

Oh! That's quieter than I thought they were. I might have to reconsider!

And lol - I'll also need a new PSU, cos ATM when I turn off ALL my fans bar the PSU fan, my PC is STILL TOO NOISY :mad:

I reckon in the next month or two I'll be spending all my money on cooling stuff ( fans, variable resistors, etc etc ). I wonder if it'll get to the stage where I get pissed off with my graphics card fan? hehe :D

[Binky Stunt Cat]

you mean ur not water cooling ur gfx card??:eek:
and my psu is about the noisest thing in my case too...but i'm considering ripping it open and replacing the fans in there with Stealths...:D

[Volodkovich]

i dont know...u guys and quiet pc's...

[KingJackal]

Originally posted by Binky Stunt Cat
you mean ur not water cooling ur gfx card??:eek:


DUDE!! Gimme a break - Tojja only finished his Pixel Ice's the other week, and I've gotta get some cash together!! :p :D

[Binky Stunt Cat]

oh ok, sorry.....gonna water cool ur northbridge while ur at it too? :P

[KingJackal]

When the ArcticNorth is released, yes.....
;)

But for the moment, it's just CPU ( the slow releasing of Tojja's product line suits my slowly raising the cash quite well :D )!

*goes and sees how cheap he can get Vantec ( or similar ) stealth fans*

[Volodkovich]

how do u reckon tojja is going to get the articnorth to attach to the northbridge when theres no holes in the mobo? conductive epoxy?

[Binky Stunt Cat]

well......i'm pretty sure that there is a similar setup for northbridges as there is for gpu's..

[_N_]

to reduce the noise, why not put a duct onto it, and have the noise coming out of into something else, eg, not your head,

or put like a cover over the fans, which looks like a box, with the bottom cut out, and have some sponge inside, and that way it would make it quieter?

[Geek4Life]

Well after reading the thread about getting your mate to bring back water pipe from California.

Why not get him to bring back a 20-25cfm fan as well ;):D :eek:

[Joshsti_NZ]

Get the Panaflows, my mate has 5 of them (80MM), 2 in front, 2 rear, 1 top, they aren't real noisy, just a little, although he has his case on the floor (on wheels) so its a bit further away than 40CM hehe ..

[Geek4Life]

Originally posted by Joshsti_NZ
Get the Panaflows, my mate has 5 of them (80MM), 2 in front, 2 rear, 1 top, they aren't real noisy, just a little, although he has his case on the floor (on wheels) so its a bit further away than 40CM hehe ..
Must be rather funny looking having a fan on top of a radiator :p

[max]

magpi manor is selling 170 mm fans on tradme:

http://www.trademe.co.nz/structure/auction_detail_expired.asp?id=1521040

http://www.trademe.co.nz/structure/auction_detail.asp?id=1523167

he has lots of them too.
The nidec one looks good:)

[max]

i think the sanyo one looks like this:

[Joshsti_NZ]

Originally posted by Geek4Life

Must be rather funny looking having a fan on top of a radiator :p

Dork!!

I meant like a top blowhole, like KJ has (on his case!!)

BTW, 'tis a nice black tower like styles was/is selling :D

[HaydenNZ]

The problem is people.. RPM vs size of the fan...

The noise you hear, is the wind...not the rotating of the fan, get rid of any air and it'd be silent, so no MATTER what anything over 100cfm is gonna be far to loud..only thing you could do is, channel the air..that'd reduce noise significantly, but its a tad un helpful for case cooling.

Essentially the bigger the fan, the slower it needs to rotate to be quiet, and by the sounds of it, the drop out voltage for tese large fans are well below what u need to run them at to keep 'em quiet

[KingJackal]

Originally posted by HaydenNZ
The problem is people.. RPM vs size of the fan...

The noise you hear, is the wind...not the rotating of the fan, get rid of any air and it'd be silent, so no MATTER what anything over 100cfm is gonna be far to loud..only thing you could do is, channel the air..that'd reduce noise significantly, but its a tad un helpful for case cooling.

Essentially the bigger the fan, the slower it needs to rotate to be quiet, and by the sounds of it, the drop out voltage for tese large fans are well below what u need to run them at to keep 'em quiet

Not quite. You're half way there.

The noise is the air being MOVED.

So with double ( or quadruple or whatever ) the surface area, to get the same airflow, the air need only travel half as FAST ( or quarter or whatever ).

Check it out sometime - the same amount of air moving through a thin pipe will make WAAAAAAAAAAY more noise than that air moving through the cross-section of say a room ( extreme example to illustrate my point ).

But yes, you're right that with the big fans motor noise is irrelevant - it's mostly air noise.

And yeah - those drop out voltages are a real pain.

BUT!!! I can take heart! At magpie manor's prices, I can afford to buy 4 92mm Panaflow's AND a 170mm ( or two, lol ), and play about for a while to thrash out the best solution. I mean - he's so CHEAP!! :eek: :)

[Geek4Life]

Originally posted by HaydenNZ
The problem is people.. RPM vs size of the fan...

..only thing you could do is, channel the air..that'd reduce noise significantly, but its a tad un helpful for case cooling.

Ofcourse you wouldn't be able to because sound travels through air ;)

But yeah it's the volume of air vs the size of the hole.

[ktulu]

Originally posted by Geek4Life

Ofcourse you wouldn't be able to because sound travels through air ;)

But yeah it's the volume of air vs the size of the hole.

Sound travels through liquids and solids as well ;)

A lot of the noise is generated from the tips of the blades (where it has the highest velocity) cutting the air.... think Helicopter blades (it's the blades cutting the air that causes the majority of he noise, not the air moving. This is the reason why high RPM fans make more noise in general (usually a higher pitch and hence more annoying noise too).

[Volodkovich]

i thought the noise was from the fan blade making a vacuum underneath the blade, and air rushed in reeal fast causing a sonic boom.

[raxmus40]

heh, u think your computers are noisy. try 4 120mm sanyos, 2 40mm, 2 60mm, 2 80mm, 2 70mm + power supply and cpu.:D

this quiet cooling is too expensive when youre sixteen.

[dumass]

i have one of the 170mm fans hes selling, the 5 bladed one

Runs at 7volts or 12volts fine I found :)

watercools my Radiator which is cooling my 1.6gigTbird and grafix card, Tbird ~ 40c

[Binky Stunt Cat]

so how has the quest for big quiet fans gone KJ?

[KingJackal]

Originally posted by Binky Stunt Cat
so how has the quest for big quiet fans gone KJ?

It's failed. There are none. There's obviously no market for them, because fan manufacturer's don't even seem to make such beasts. If you're talking 20cm fans, then 50dB is quiet :rolleyes:. Try 20 ish for what I want....
:(

So I'll just be buying a battery of 92mm's ( 4 of em <TIMTEHTOOLMAN> ARGH, AARGH, AAARGH </TIMTEHTOOLMAN> ) :D.

So don't be thinking about bringing small animals to L3#8 - cos in my true g[H]3770 stylez, I probably won't bother with guards.... :o

[Binky Stunt Cat]

so no array of vantecs then?

[Volodkovich]

why cant u run a car rad fan at real low rpms?

[CommanderK]

I think this is my kind of fan, http://www.sunon.com.tw/product/ac/ac25489.htm. But seriously if I was to get 2 of them for my yet-to-be case (one at the back, one at the front), would 600-700 CFM be too much (I mean I dont want the cards coming out :eek: )?