Nexus 120/92mm PWM now available.

[Bluefront]

At Jabtech. No doubt this time....it's a Yate Loon. The model # indicates as such. It lists a nice rpm range of 500-2000. And a low db rating.....probably realistic, unlike some other brands. Will this fan remain the top-rated 120mm.... we'll see.

D12SL-12 PWM
120x120x25mm
Clear chassis and foggy rotor/blades
4 pieces purple ultra-soft silicone fan mounts

500 ~ 2000 RPM (±10%)
From 15.5 dB(A)*
Up to 76 CFM

[JaYp146]

Clear frame/blades? Hmmm ... thought that clear plastic was detrimental to the "whole silencing fans" goal. At least that's what I remember reading..

[Felger Carbon]

And a low db rating.....probably realistic, unlike some other brands.
500 ~ 2000 RPM (±10%) From 15.5 dB(A)

Lessee here: 15.5dBA @ 500Hz. Double the RPM, add 18dBA, so 1000RPM = 33.5dBA. Double the RPM, add 18dBA, so 2000RPM = 51.5dBA.

51.5dBA? Yeh, real quiet fan. Hey, is that last line on the fan label "Made in China"? My non-PWM YLs don't have that on the label.

edit: the Jab-Tech listing makes it clear that the "15.5dBA" was made right up against the noise floor. So it's likely the 2000RPM noise figure is lower than 51.5dBA. But we don't know how much lower because Nexus, following in Thermaltake's footsteps, chose not to give us the actual 2000RPM noise because it would be a lot higher (heaven forbid that the sucker/consumer have actual useful data!).

[hiower]

Bump.

I am also interested in these fans. Does anyone have any experience with them?

[hiower]

And a low db rating.....probably realistic, unlike some other brands.
500 ~ 2000 RPM (±10%) From 15.5 dB(A)

Lessee here: 15.5dBA @ 500Hz. Double the RPM, add 18dBA, so 1000RPM = 33.5dBA. Double the RPM, add 18dBA, so 2000RPM = 51.5dBA.

51.5dBA? Yeh, real quiet fan.

Can I ask from where you take those numbers? (Double RPM = +18dBA)
Also, do you know any fan that is quiet at 2000RPM?

Taking the SPCR review of the Scythe S-flex as an example, test results showed <19 dBA@1m at 5V (550rpm), but only 23 dBA@1m at 9V (1190RPM). Using your calculations, S-Flex at 1100RPM should have been at least 35dBA. (Double RPM = about +18dBA)

[Greg F.]

Isn't that a little much? Can you daisy chain other PWM fans onto this one or is that something you can just do with the Artic Coolings I was looking at on the egg? Thanks for posting this.

[Felger Carbon]

Taking the SPCR review of the Scythe S-flex as an example, test results showed <19 dBA@1m at 5V (550rpm), but only 23 dBA@1m at 9V (1190RPM). Using your calculations, S-Flex at 1100RPM should have been at least 35dBA. (Double RPM = about +18dBA)

The SPCR test facility has a noise floor of ~18dBA. Even if you unplug the fan, SPCR will still measure ~18dBA. If both dBA readings are well above the noise floor, a 2-1 RPM difference will result in an 18dBA change in noise level.

SPCR religiously takes all fan noise measurements at a distance of 1 meter (39.37" for us furlong-per-fortnight folk), which makes the noise floor more of a problem. (Ahem) I take fan noise readings as close as 1/4" if the noise floor is a factor.

You can ask Jaganath about the 18dBA per doubling RPM factor. He once really raked me over the coals over that one, and he had some help. Nobody who's been here at SPCR awhile disputes that figure now. Jaganath can explain why.

[hiower]

In other words, adding 18dBA to the 15.5dBA at 500Hz is not valid, as it is not well above the noise floor?

Also, your post make me think that the +18dBA formula is only valid at certain distances? (if it is valid, I still have seen no proof for that )

In that case, to me, the measurements at 1m away would make more sense, as it is not likely that one would be as close to the fan as an inch away anyway.

[Bluefront]

Frankly....I prefer FC's way of measuring fan db (up close), since it eliminates ambient sound (which varies) from the measurement. This would give anyone the ability to preform fan noise comparisons, even if he lacked a "quiet" room.

FWIW....there is a 92mm Nexus PWM fan now available. I don't think this one is a Yate Loon.....because of the Model #.

[HAHA]

I have had all three (80, 92, 120) of the new Nexus PWM fans in possession for a couple of days. I have been trying to perform measurements for a little review but man - it's difficult to be scientific without a proper testbed.

My plan was to use my rather silent PC (all passive except Seasonic PSU) and its' motherboard to drive the fans. This is the only PWM-driver I have at the moment. I have reasonably good sound recording equipment but no way of measuring air flow. I also have ordinary Nexus 80, 92 and 120 fans for comparison and I have tried to mount them outside the PC in free air. I have tried to do recordings at different RPMs for all fan sizes and types. I have also tried to judge the airflow with a simple device held in the air stream. I though I got it right the third series of measurements but now I found out that my way of mounting the fans caused vibration induced noise.

So now I have to do it all over again and might as well ask you guys for advice on things like microphone distance and placement relative the fans.
I also need some way to suspend the fans. Taping them to the top of the PC chassis wasn't good enough...

Preliminary findings are that the new PWM fans are about as silent as the classic ones for the same RPM. They sound slighly different but they may also pump slightly more air at the same RPM. This may have something to do with the MB tachometer accuracy though. The 92 mm PWM has a different blade design from the classic 92 mm. All fans (80, 92, 120) have different blade designs from one another.
My ASUS P5KE can't stop the PWMs completely from Speedfan as far as I have seen. I can stop them by hand and it stays still for a while but suddenly it seems to get a little extra pulse of power and it starts up again.
The classic fans do not behave like that.

[Felger Carbon]

I can stop them by hand and it stays still for a while but suddenly it seems to get a little extra pulse of power and it starts up again.
The classic fans do not behave like that.

The Intel PWM specification requires that the PWM fan be restarted (or an attempt made) periodically. The A-C and Scythe PWM fans appear to be mostly designed in accordance with that complex spec. Some other PWM fans aren't, for what it's worth.

[Access denied]

And a low db rating.....probably realistic, unlike some other brands.
500 ~ 2000 RPM (±10%) From 15.5 dB(A)

Lessee here: 15.5dBA @ 500Hz. Double the RPM, add 18dBA, so 1000RPM = 33.5dBA. Double the RPM, add 18dBA, so 2000RPM = 51.5dBA.

51.5dBA? Yeh, real quiet fan. Hey, is that last line on the fan label "Made in China"? My non-PWM YLs don't have that on the label.
.

nice one.. or, NOT

next time check what they say before u say somesthing:
http://www.nexustek.nl/NXS-120mm-pwm-fa ... -quiet.htm

[Felger Carbon]

next time check what they say before u say somesthing:
http://www.nexustek.nl/NXS-120mm-pwm-fa ... -quiet.htm

Information is a good thing to have. Do you know on what date that data was posted by Nexus?