http://smiliesftw.com/x/bigbowrofl.gifQuote:
Originally Posted by leathal
Printable View
http://smiliesftw.com/x/bigbowrofl.gifQuote:
Originally Posted by leathal
It's true.Quote:
Originally Posted by Vapor
The aircraft companies they could make a helicopter as quiet as the new Comanche is until they experimented with the main and tail rotor design. They don't use the same blade technology as you find in other helicopters from years ago and new ones today. Basically the point is the blade shape, size, and number of blades determines the noise level as well the air flow so it's not like this is anything new and unheard of, you just have to wake up and smell the coffee! :)
I would use the new FLEX 1900 rpm fans not terribly loud and moves decent air.
points of dimishing returns 400 rpm fans moving barely any air or on the flip side 252 CFM fans
quiet but hot or noisy and cool
I mean hell might as well go phase change the wattage alone on those high speed fans could power a small compressor LOL
Whatever helps you sleep at night.Quote:
Originally Posted by leathal
LMAO this thread is going downwards. If u really belive 19db\90cfm.... well.
Even without the fan itself, just the frame. 90cfm moving through a 120mm hole is produsing more noise than 19db. Add the fan wich is actually producing thoose "90cfm" and ur at helluwa lot more than 19db. Well... unless ur taking the reading in another room.
I dont know how sensitive your ears are but most of the small amount of 12cm fans I tried before start buzzing above 1000-1300rpm regardless of which brand or blade they are.
All I can trust is the majority oppinion of the user of the fans.
BLAHHH 57.6W per fan you could power a 1/5 hp phase unit off 3 of those fans cooling the TC120.3 rad
oh check out this video think you can live with the noise??
http://www.youtube.com/watch?v=PDzVJKRkQB8
http://www.youtube.com/watch?v=ZaWw33wz_O4
my flex-E are pretty quiet at 1200 rpm
Yes, as a rule of thumb(or whatever they call it) u can look at the rpm to know how much noise it makes... ish. Rpm counts way way more than the blade design when it comes to noise.Quote:
Originally Posted by Sparda
If u find a fan design wich lowers the noise quite abit at a given rpm, i bet my ass that u also lowered the cfm at the same time.
I have the 2500RPM version of the fan right here. I also happen to be in the middle of testing other fans--I'll put them on hold for a few minutes and give this one a whirl.
Okay, test results.
12V (2500RPM) numbers:
82CFM @ 43.9dBA
10V (~2250RPM) numbers:
73CFM @ 40.9dBA
Few notes...the fan never gets really quiet, even at 5V. Makes this rasping/grinding noise, might not be noticeable in a case though. The turbulence noise is especially bad above 8V...below that the motor noise takes over. And most of all...even the 2500RPM version doesn't hit 90CFM. Interpolating from this data, the 2000RPM version should move approximately 65-66CFM and at an unpleasant ~38dBA.
Of all the fans I've tested so far on this testbed...the best performance at ~19dBA was the Yate Loon D12SL-12 @ 5V moving just under 26CFM (@19.3dBA). My previous tests can be found in the stickies of both the Liquid Cooling and Air Cooling sections.
In other news, I'm shocked at how bad this fan is...
Pretty conclusive id say. Not a good fan at all then.
Correct, and with the bigger fan OEM's getting into advanced blade and motor designs hopefully we'll see a long overdue change in fan tech. I bought Noctua based specs and reviews and I haven't been disapointed. I just slapped in two Enermax "Magma" fans for top exhaust and feature\performance wise they're pretty cool too, detachable blades for ease of cleaning, bat wing blades and a very interesting motor.Quote:
Originally Posted by leathal
Still, its only minor changes. Nothing major. look at Vapors fan testing. at the same rpm (and same fan size ofc) there isnt any real big differences, only minor ones. And Vapor has testet quite alot of fans. Shure, blade design (straight, curved, golf balled) do make minor changes, but in the end the rpm makes alot more change.
Whether the difference is minor or major depends on what the individual requires from said fan. For me, trying to build my first "quiet" rig, I wanted performance without a lot of noise. The Noc's I picked delivered on a few levels, and not just because they're 1300RPM. Blade design DOES help to a tangible degree in my case. :up:
Blade design is a big part of fan design, but in the instances we are talking about here, with this 90cfm/19db fans, its just an outright lie. You could have a bunch of spinning celery sticks and it still not gona produce what is being stated in the specs.Quote:
Originally Posted by John Planet
Yeah, at this point I've tested about 70 fans (unique fans...if you count all the duplicates and all the ones for my own uses, it's nearly 100 fans).
No doubt each design point has an influence and there have been advances. But simply, there's no magic fan. There's no fan that's leaps and bounds better than everything else (it would be mimicked immediately anyway). There are, however, fans that are magically bad (ironically, they're usually the ones that proclaim superiority--this Cooler Master might count as that bad....the SilenX are definitely in that category at least).
RPM can tell you so many things. Or at least tell so many things it's not.
i recall the gap between 2 blades determine the MOST dBA ..
the larger the gap .. the quieter (aka Notua) .... the smaller the gap ... the noiser (9 bladed ones)
but .... the larger the gap ... the less air pressure (bad for rad) ... the smaller the gap .. the better air pressure (good for air restrictive rad)
other than that .. the rotor .. i dun know how to measure ... but i do use vaseline - petroleum jelly as grease around the "ball bearing"? (i dun know what it's called) .. it just reduce slightly (just slightly) the sound in lower rpm .. but still the same sound in max rpm
i didnt use any measurable device to measure the dBA .. just a quiet room, closed room in dead night
hope this works
and in your opinion what are the best ones? (top5 of your list)Quote:
Originally Posted by Vapor
If dont remember wrong, i think yates(petras) and scythe s-flex is pretty high up.
San Ace H1011
:D Perhaps. I'd wait for a commercial review, or someone like Vapor, before I made a final decision, though.Quote:
Originally Posted by Spawne32
I believe noctua p12's pulling through a shroud would be all you need, and very quiet at the same time.
I've gone the noisy fan route before and it sucks. The bling gets old too.:2cents:
Attachment 82028
Attachment 82029
Attachment 82030
Yup, I'm running 6 P12's on my rad and I'm very pleased with the results. :cool:Quote:
Originally Posted by dengyong