Okay...fans....I have 12 external (case) fans, 1 for my Ultra-120 eX, 2 for my IFX-14, and 1 for my HR-03+. So that's 16. I happen to have a little experience with fans and I know at least this much: when you have a lot of fans, some will be bad apples.

I also know a few other things: noises you can't hear are often the most annoying. May sound like some cryptic thing you'd find in a fortune cookie, or you may think I have voices in my head, but I assure you neither are the case.

What I mean is this: we have cases for various reasons...among many reasons: animal/kid proofing, aesthetics, portability, and noise proofing. When a fan makes a slight murmur or a faint click, chances are the noise will not leave the case. You will not hear it from a few feet away through a metal box. Granted, any sort of loud click or scuffing you'll hear, but minor noises can be dismissed. What is of large concern is when the fan impacts the metal box.

We've been getting around that with silicone gaskets (which I will be using), silicone screws, silicone sealant....just about everything silicone except Pam Anderson. But the root cause is the fan and is actually fairly easy to remedy. The remedy also allows for a build with fans that don't scuff, murmur, or click in the slightest

1) The fans

Here are 14x Yate Loon D12SL-12s, 4x Yate Loon D12SM-12s, and 4x Sanyo Denki "San Ace 1011s"


They're the principle fans I'll be using in this build, and for good reason:
1) Yate Loons (REAL ones from Petras) are VERY good fans. They are not the best, but they're damn close. They come with flexible wiring options and have a very plain all-black design (except the stickers). Oh, and they're only like $3-4 a pop.

2) Yate Loon SLs push their rated 47CFM (actually, a tad bit more on average) and are fairly quiet. At 5V, they're well below the noise floor of my dorm room (heck, at 12V, a bunch of them are still below the noise floor when I have my A/C on).

3) Yate Loon SMs push well below their rated 70CFM (the highest I've ever seen over 5 different samples is 55.1CFM IIRC). Their CFM levels (54ish) are very close to the SL's 47CFM, which may scare some people away, or many just may find them irrelevant. However, they do have a purpose for my build: balancing airflow at my various voltage 'presets' (12V, 10.5V, and 5V).

4) San Aces are just incredible at 12V and 5V, but expensive at nearly $20 per fan. Hence only being used on the HSFs.


2) The fans need some work.

First, Yate Loons have a lot of wire connected to them....I'll be using 3-pin connectors throughout, so I can ditch the double-molex. Also, even up to the 3-pin is fairly long. So while I had plans to sleeve (and would still like to), I'll only be braiding the wires for now. It's not that big of a deal, as I have no windows in my case, but it's something I set out to do and I've bought a lot of sleeving materials and even had Alex from Petra's Tech Shop dig in his warehouse for a length of very narrow heatshrink as the included wasn't shrinking very much. I feel I owe it to him for being such a good sport and to myself.

In the meantime, I've braided them (and lost an SL and a San Ace in the meantime ).

(the Yate on the right in cootie-land is the one I messed up on the wiring and do not feel comfortable putting into a system 24/7).

I've also removed all the stickers (front and back) to make the fans all-black. On the back, in order to seal the motor, I've applied black electrical tape.

The San Aces, other than having their wires braided, are unchanged (internal only after all).

Now, I started with 18 case fans, (down to 17 now), but I only need 12. Why is that?


3) The Cure

Let's face it, fans aren't perfectly identical, some exhibit unwanted noise, others just don't spin at their rating, and some are just perfect. Real Yate Loons, although inexpensive, are very good fans and typically are very consistent.

I also have the luxury of being able to test fans empirically.

All things considered, empirical dBA testing was out of the question for me at this time, but CFM testing is easy and my ears are as trained as anybody's. Plus, I have another test up my sleeve.

First, I had to identify what made a good fan and where I wanted my fans to 'run.' Ultimately, if you plan on running a fan between 5V and 7V all the time, why should you care how it performs at 11V? No need to really. May be nice to know I suppose, but it's not critical. I identified the three voltage points my fans will always be running at: 12V (12V switch setting), 10.5V (rheobus max), and 5V (5V switch setting AND rheobus minimum). I really doubt I'll ever have a fan at a middle-ground setting on the rheobus.

Next, because all the stickers were removed on the Yates, I had to label all of them at the connector. Fortunately I did this before I removed the stickers though As I said, I lost an SL, so "L7" is absent from testing.

How I tested:

1a) Does it startup on the 5V switch setting?
1b) Does it startup on the (5V) rheobus minimum?

2a) CFM at 5V (switch)
2b) CFM at 10.5V (rheobus max)
2c) CFM at 12V (switch)

3) Subjective noise rating (letter-grade style) on the rheobus (where more problems are likely to exist).

4) Vibrational tendencies (letter-grade docking).

Startup tests are easy....if I have to explain those, please leave XS.

CFM tests, I used my very familiar anemometer setup and got very consistent results. Old news. None of the voltages were checked, as ultimately I won't run it that way....I just used the 12V switch (12V rail), the 5V switch (5V rail), and the rheobus's max (on the same channel for testing).

For the noise tests, both close-range and distant subjective noise testing was done. I listened for both unusual noises and amplitude. I also tried to target any sort of noises that may become a problem in the future.

Vibrational testing I thought was rather creative. First I'd stand the fan up so it was only standing on a 120x25mm side with the wire sticking straight up. Then I'd torque the wire so that it pulled on the fan slightly (wanting to twist it) and then I also aimed the fan to blow against the torque (helping it twist even more). I'd turn it on for 12V and watch the fan crawl across my desk. Every fan moved across the desk, but the ones that veritably shimmied or chattered their way across were the ones I was looking for.

Findings: only one of my fans exhibited any sort of extraneous noise. "M1" is a proper nomer for what it did to my ears. Okay, it wasn't so bad, but among a bunch of straight-laced fans, this murderous little guy was a standout. Only one of my fans exhibited any sort of chatter. "L1" was the problem fan and I have no joke for it. Interesting that both my "1" fans were the only big problem ones (numbers were arbitrarily assigned).

Even the slightest shimmy or murmur was docked considerably (2/3rds of a grade). If I even thought a fan was slightly louder than it should be, I'd dock it either 1/3rd or 2/3rds, subjectively.

Here are the results (red = will not be used, green = a 'go', yellow = definitely good, not sure what I should do with it):


Now that I have my fans selected, the next major update will be the airflow layout. After that, the grand finale: the case arrives and will be used.