Noctua Introduces 120x15 A-series fans - Finally!

Aibohphobia

aka James
Feb 22, 2015
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Most airflow happens towards the blade tips since that's where the angular velocity is highest. So a bigger hub isn't necessarily a problem.
 

LocoMoto

DEVOURER OF BAKED POTATOES
Jul 19, 2015
287
334
Some quick very subjective notes on the fans...

The type of noise they produce is quite smooth to me, neither very low or high in the frequencies, overall air noise from the lower to higher RPM feels less than the NF-F12s, at 700RPM I feel very happy with the lack of noise compared to the NF-F12s, and they have worked more consistently with noise than the Big Shuriken 2 fan at the same speed, they fit quite well with the standard Scythe fan clips, moves more air at the same speed as well (Noctuas are 15mm thick vs the Scythes 12mm on the other hand though (duh))

Haven't gotten any temp results on the cooler though, since I've been quite busy lately
The exposed hub piece is also, so attractive according to me, not a fan of the included rubber mounts, I do like the ones that came with the NF-F12 much more!
 
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ceski

Deleted account per user request.
Feb 28, 2017
234
5
You mention Scythe slim fans burning up as a well known problem, but this is the first I've heard of it. Sleeve bearing fans may wear out faster when mounted horizontally, so maybe that was the problem?

Also, have you guys considered investing in some test hardware? You can actually pick up a good mic kit (flat response, noise floor <20dBA) and an anemometer for way under "tens of thousands" (closer to $1200 USD). If you wanted to get fancy, you could even make a diy anechoic chamber and an air flow chamber for a couple hundred more.

Apologies for the rant, but the review seemed light on data (RPM curves are free!).
 

Aibohphobia

aka James
Feb 22, 2015
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4,682
You mention Scythe slim fans burning up as a well known problem, but this is the first I've heard of it. Sleeve bearing fans may wear out faster when mounted horizontally, so maybe that was the problem?
The short axle length compared to the fan blade diameter on slim 120mm fans puts more stress on the bearings. It's the same problem with 200mm fans, which is part of why it took Noctua so long to release both.

John has personally had the bearings on several of those Scythes burn up on him. Jakob was too polite to name names, but like any company developing a new product Noctua did testing on the existing competing products, and when John mentioned the Scythe bearings issue Jakob smiled and nodded knowingly.

You can actually pick up a good mic kit (flat response, noise floor <20dBA) and an anemometer for way under "tens of thousands" (closer to $1200 USD).
The Josephson C617 looks promising, with 14dBA self-noise for around $2k. And the SF101a looks like a really good value at $900 for 13dBA. From my research though, it seems that it'd be better in the long run to spend the extra money for a 1" capsule for the best low noise measurement capability.

So I've been eyeing the ACO Pacific PS9200KIT with either the 7022 (what SPCR uses) or the insane 7020 capsule (2dBA self-noise!!!) but that's about $2500 or $3000 respectively. BTW, Google is saying their website may be hacked right now though, so probably shouldn't visit it.

Besides the microphone/preamp, an audio interface, analysis software, and calibrator are needed as well.
 

ceski

Deleted account per user request.
Feb 28, 2017
234
5
I can vouch for ACO Pacific, very friendly and helpful. He even recommended some accessories from other companies to help me save money. I've used the PS9200KIT with a 7046 and it's great. Due to time constraints, I paired it with SpectraPlus and SpectraDAQ-200 as the interface, but you can save a lot of money using TrueRTA and a second hand interface. Calibrators are cheap on Amazon/eBay.
 

Aibohphobia

aka James
Feb 22, 2015
4,955
4,682
The 7046 is something I considered as well. Do you know if the 12dBA noise floor is realistic? I notice that ACO Japan's specs are more conservative than ACO Pacific's so I'm a bit skeptical.
 

ceski

Deleted account per user request.
Feb 28, 2017
234
5
I suspect they're overly optimistic, plus it doesn't consider the entire test equipment chain. The chamber I've tested in only goes down to ~18dBA (at night) so I can't validate below that. That's part of the reason I went with the 7046 (and is mostly used for louder measurements of unrelated devices; the PC stuff is weekend fun). You'd need to go full SPCR mode and construct an anechoic room to get a lower ambient.
 

Aibohphobia

aka James
Feb 22, 2015
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You'd need to go full SPCR mode and construct an anechoic room to get a lower ambient.
Getting proper load testing equipment for PSU reviews would cost several thousand dollars, but there are already several sites doing good PSU reviews and while they take longer than I'd like, they cover SFX and SFX-L too.

Building a low-noise rig for ATX is pretty easy these days, but it's far from a solved problem when you start talking high-performance SFF. So I've been leaning towards investing in a sound measurement setup instead since there isn't an alternative to SPCR that's active.
 

confusis

John Morrison. Founder and Head writer SFF.N
SFF Workshop
Editorial Staff
Moderator
Jun 19, 2015
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I live in the middle of my country's biggest city, noise measurement is a pain!

Regarding RPM measurement - I refuse to report motherboard reported RPM and PWM values, especially considering that I run a Gigabyte board in my personal rig! I am currently working on an arduino based PWM testing rig for proper logging, including RPM measurement every 5 PWM steps,

The other issue that I come across is time - I work 40 hours a week (in retail -_-), and am a solo parent to two (awesome) kids - I need to budget testing time after dealing with those - this review is already a month late (although Computex did eat a couple weeks of that).

TLDR; I'm working on making my content more detailed!
 

Broxin

Cable-Tie Ninja
Jun 16, 2017
167
131
THE fans we've all been all been waiting for are finally here!

Noctua have just announced they are currently shipping out their new lineup of premium quiet fans which include the highly anticipated 120mm x 15mm models:

NF-A12x15 PWM

NF-A12x15 FLX
how should i decide on which one to choose? pwm or flx?

if i have a mobo that is capable of controlling a pwm fan, would it make sense/be better to use a voltage regulated flx fan instead?
pros/cons?
 

Aibohphobia

aka James
Feb 22, 2015
4,955
4,682
if i have a mobo that is capable of controlling a pwm fan, would it make sense/be better to use a voltage regulated flx fan instead?
For a PWM CPU header always get a PWM fan. For chassis headers if the motherboard has a particularly bad fan control implementation it could potentially make sense to get the non-PWM fan if the controllable voltage range is more desirable than the controllable PWM range.

Which motherboard is it? Chassis header PWM wonkiness is mostly behind us from the big names for the current generation.
 
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Broxin

Cable-Tie Ninja
Jun 16, 2017
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131
its an asus z270i, where i saw that every header can be switched from pwm to voltage control so i am curious which to choose.

wasnt it in the past that pwm fans are more noisier because of the pulsing ?
 

Aibohphobia

aka James
Feb 22, 2015
4,955
4,682
its a asus z270i
Okay, current-gen ASUS is about as good as it gets for motherboard PWM headers. No reason to get voltage control.

wasnt it in the past that pwm fans are more noisier because of phe pulsing ?
That's somewhat true, some fans have poor PWM implementations and I think some people have complained about the Industrial Noctuas due to the 3-phase motor design.

But Noctua's consumer fans, like the NF-A12x15 PWM, have great PWM implementations so there's no reason to get the FLX version for your motherboard.
 
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EdZ

Virtual Realist
Gold Supporter
May 11, 2015
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Regarding RPM measurement - I refuse to report motherboard reported RPM and PWM values, especially considering that I run a Gigabyte board in my personal rig! I am currently working on an arduino based PWM testing rig for proper logging, including RPM measurement every 5 PWM steps,
Alternatively, an optical tachometer and a small piece of retroreflective tape (or even a dot of white paint) will give a real-world RPM measurement even if the PWM reported speed is for some reason incorrect.
 

chx

Master of Cramming
Silver Supporter
May 18, 2016
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With the aforementioned airflow vs pressure issue... would two of these work well with a Noctua C14S?