Directron's 80mm fan comparison

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BaconTastesGood
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Directron's 80mm fan comparison

Post by BaconTastesGood » Wed Jan 01, 2003 8:57 pm

Any comments/opinions? The Panaflo rates fairly poorly.

http://www.directron.com/noise.html

Zyzzyx
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Post by Zyzzyx » Wed Jan 01, 2003 9:16 pm

I guess I'm too damn cynical, but I look questionably that their own branded fan came in second, a good deal ahead of the majority of the fans.


that, and I didn't see any pictures (that they mentioned even) showing their testing setup. Description yes, no pictures.


<shrug>

I'm figgerin that most any fan at 5V is gonna be quieter than even that Enermax at 12V.


Zyzzyx

BaconTastesGood
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Post by BaconTastesGood » Wed Jan 01, 2003 9:37 pm

While I understand that the intent was to measure relative performance, I think it's a bit misleading to also place the microphone 1cm (?) from the fan. That seems like there would be large opportunity for things like proximity effect, etc. Also, if two fans are effectively identical at 1M but one is significantly louder at 1cm, does that matter?

I equate it to benchmarking a graphics card. If it scores a 3DMark twice that of another one, but both run Quake3 at 120fps, does it matter?

powergyoza
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Post by powergyoza » Thu Jan 02, 2003 2:05 am

http://forums.silentpcreview.com/forums ... .php?t=152 has a critique of their testing methodology. There are 3 main beefs: 1) thermally controlled fans not likely tested at full speed, 2) cfm not accounted for, 3) mic positioning not clear.

Ralf Hutter
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Post by Ralf Hutter » Thu Jan 02, 2003 5:37 am

Directron's testing methodology was also shot down either at Ars or Anandtech a few months ago when this article was first published. Use the search on their forums to read all the juicy discussion.

ez2remember
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Re: Directron's 80mm fan comparison

Post by ez2remember » Thu Jan 02, 2003 7:35 am

BaconTastesGood wrote:Any comments/opinions? The Panaflo rates fairly poorly.

http://www.directron.com/noise.html
I have seen this question asked before, elsewhere in the forum. Check it out and it says why the test was not conducted properly. :D

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Post by powergyoza » Thu Jan 02, 2003 12:31 pm

Directron's testing methodology was also shot down either at Ars or Anandtech a few months ago
I was curious myself, and found the juicy stuff here:
http://arstechnica.infopop.net/OpenTopi ... 2020951035

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The test is limited and somewhat flawed, too

Post by NeilBlanchard » Thu Jan 02, 2003 7:18 pm

Hello:

I read this test a while ago; well before I had come upon this site. And at the time I found it frustrating partly because it sets out to be a "scientific" test, and then in the end, it is so vague and inconclusive. I'm glad for the description of the method -- I'd bet a dime against a $1 that the meter that they were basing the whole thing on is the Radio Shack digital sound level meter. I own the analog RS meter (which is the same except for the meter/readout, AFAIK), and it is useful for some relative measurements, but it is hardly absolute.

Another hobby that I have since stopped pursuing as a hobby is music and hifi audio, and I used my cheap little RS meter to help tune the bass on my Snell Acoustics Type E II's. The microphone element in the RS meter is hardly a flat response item -- somewhere in this messy office where I am, there is/was a printout of the *known* errors, nevermind the individual error that is always present in mass produced anything -- including fans!

So, how does this relate to the subject at hand? Well, taken for what it is, the Directron test has some useful *relative* comparisons, but the gapping holes include no comparisons of CFM and the inclusion of thermally controlled fans (each with totally different thermal/speed curves!!) limit it. So, what does it tell you? That some fans have more noise from whatever source, be it mechanical, bearings, turbulance, or just plain old moving air! That's it.

I think that any truly useful test would COMBINE these sorts of measurements with subjective tests. Say what? Yup, our ears are what are going to be the final judge -- because even if you bought the "quietest" fan, it might have a sound that drives you nuts. Or, it might move a totally inadequate amount of air. The bottom line is: can you hear it, and does the noises it makes "work" for you -- and does it keep your case cool enough?

BEFORE I had read the Directron test (I don't think it had been published), I had bought (from Directron) one of the (supposedly) 12dBA Papst 80mm fans and one of the Silencer 80mm jobs. (It's NOT Directron's fan, BTW. See the post above.) The Silencer made *slightly more noise than the Papst, but it also moved about twice as much air (based on my totally scientific hold-your-hand-in-front-of the-fan methodology :-)) and at the time, the Silencer was about half as expensive, to boot. So for me, the Silencer makes more sense, and is a much better value.

Both fans went into a "work" machine that was even too loud under the desk. The Papst went in the front as the intake, and the Silencer went in the back, and both screamers went into the box. The stock (5000RPM?) fan on the Athlon XP 1800+ (Palomino) was then the loudest thing in the case, followed by the 80GB Western Digital and the 350watt power supply. It was still somewhat noisy, but you could still think when it was running, and there was not so much the great relief when it got shut down anymore. And it remained perfectly stable, which is the point, really.

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