new Scythe Kama Flex, other 92mm fans at equal airflow

Felger Carbon · Post by **Felger Carbon** » Thu Mar 27, 2008 4:41 pm

Scythe Kama Flex 1600RPM, SilenX "11dBA" 92mm fan, Arctic Cooling AF9225 fan, GlobalWin NCB 92mm fan, Nexus Silent 92mm fan. All recently purchased. 30dBA SLM range used for noise measurements, ambient noise <30dBA, 1/4" microphone distance. Airflow sensor propeller RPM 695 for all fans (equal airflow).

Code: Select all

Kama Flex      9.26V 45.1dBA 695RPM 1286RPM
new SilenX"11" 8.61V 46.1dBA 695RPM 1153RPM
A-C AF9225     6.60V 48.8dBA 695RPM 1390RPM 
GW NCB         9.97V 49.6dBA 695RPM 1596RPM 
Nexus Silent   12.0V 52.1dBA 695RPM 1553RPM

Looks like the Kama Flex bearings are, as advertised, really quiet, although in my opinion the high pitch - second only to the SilenX - contributed most of the "quiet". The Kama Flex is 1dBA quieter than the SilenX, and 7dBA quieter than my sample copy (newly purchased and unused) of the Nexus Silent. Looks good to me!

(The less fan RPM needed for the equal airflow, the higher the fan pitch.)

aztec · Post by **aztec** » Thu Mar 27, 2008 10:45 pm

Thanks for that Felger!

I think I've found 2 fans for my NSK3480 build. Probably overkill, but nonetheless.

BTW. PPC has these fans in stock

floepie · Post by **floepie** » Sat Mar 29, 2008 10:02 am

This doesn't necessarily tell you how they would perform under lower CFM needs, would it? Could it be that when the Nexus is @ 7V, and airflow amongst all fans is held constant, that the Nexus then becomes the most quiet? Or, are you suggesting that this new fan becomes the best choice for 92mm fans?

Felger Carbon · Post by **Felger Carbon** » Sun Mar 30, 2008 8:50 am

floepie wrote:This doesn't necessarily tell you how they would perform under lower CFM needs, would it? Could it be that when the Nexus is @ 7V, and airflow amongst all fans is held constant, that the Nexus then becomes the most quiet? Or, are you suggesting that this new fan becomes the best choice for 92mm fans?

Last question first: I present some data, carefully taken on samples of commercial (in this case 92mm 3-pin) fans. I have not tested other samples, nor all fan makes and models, nor have I tested at all RPMs or under different backpressure. There isn't time and money enough in the world to do all those things. If the limited data I present is of use to you, good. If not, ignore it.

Note that I'm measuring noise at 1/4", not at one meter, to get up out of the ambient noise mud. At a CFM equal to the Nexus at 7V, I'd be at about 30dBA even at 1/4" and the noise data would be useless.

So, answering your first question, the answer is no. I don't know where you could get the comprehensive data you want anywhere in the world. If you find it, please alert the rest of us to the info. I'd like to have it myself.