Build the perfect fan - tell us what you want

Control: management of fans, temp/rpm monitoring via soft/hardware

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Bestbyteinc.com
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Build the perfect fan - tell us what you want

Post by Bestbyteinc.com » Wed Apr 13, 2005 2:22 pm

We recently started offering Nexus fans at our online store in response to requests by some Silent PC Review forum members. They run at unusually low speeds but are otherwise unremarkable and very overpriced. These Nexus label fans sell for $12-$20 it seems while we can offer comparable models for under $1 for 8cm or under $4 for 12cm. We stock hundreds of different fan models and custom order unique fans built to customer specifications. Why not design the perfect Silent PC fan yourself? We'll offer it for half the price of Nexus (or less.)

We are seeking input from hardcore silent PC fanatics about the ideal silent fan. Once we can reach some sort of consensus we will prototype the top selections, measure noise, choose packaging/labels, and submit for official review.

Here are some factors to consider. Please specify for 120mm, 92mm, and 80mm sizes:

*Most important: specify ideal RPM for each size
Compare Nexus fans 120mm@1000RPM, 92mm@1500RPM, 80mm@1500RPM

Preferred thickness (25.4mm or 38mm)
Fan material
Fan color or colors
Bearing type
RPM
Constant or variable RPM
Temperature control (Y/N)
Sensor location/type
RPM signal output (Y/N)
Locked rotor alarm (Y/N)
Autorestart (Y/N)
Power connector
Lead length
Lead wire colors or sleeving color
LED Yes/No
LED locations/colors

Other special features, anything at all. Examples of special features would be detachable leads, detachable on/off switch, speed adjustment knobs, LED on/off, or any other crazy thing you would like to see.

This is all about giving you what you want- so tell us!
Last edited by Bestbyteinc.com on Wed Apr 13, 2005 7:09 pm, edited 1 time in total.

frankgehry
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nexus qualities

Post by frankgehry » Wed Apr 13, 2005 3:06 pm

Hi BestByteInc,

Just to start off, Nexus fans are quite remarkable in that they are the quietest fans I know of. They are also very consistent from sample to sample - you don't have to buy 3 to get one good one. Each model, the 80, 92, and 120 is produced by a different manufacturer. One model is made by dynatron or top motor. You can probably build a fan with nexus specs and still end up with a design that does not match the subjective qualities of nexus. - FG

The specs that really matter are noise levels, lack of bearing noise, and cfm. As you mentioned the other specs or features of nexus fans are not that remarkable.

I do think its a great opportunity for spcr readers to have the ear of a company like BestByteInc.

EDIT:

80mm = bi-sonic
92mm = dynatron|dynaeon|top motor
120mm = yate loon

Thickness - 25.4mm
Fan material - heavy stable black plastic

120mm = RPM - model L = 1200, model M = 1650
92mm = RPM - 1800
80mm = RPM - 1800

Bearing type - Ball? (I'm not convinced anymore that sleeve bearings are better than good ball bearings)

Constant spd.
No temp. control
RPM sensing
Locked rotor alarm
Auto restart
3 pin or 4 pin with PWM fans
Lead length - 12"
lead colors - yellow, red, black
LED - no

Some of the other features might be nice but holding down the price and producing a stripped down model with quality materials, bearings, build quaility and motor are most important to me.
Last edited by frankgehry on Thu Apr 14, 2005 3:44 am, edited 4 times in total.

Bluefront
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Post by Bluefront » Wed Apr 13, 2005 3:23 pm

OK...here's what I'd like. A 120mm fan, sleeve bearings, similar to a Globe model S1202512L-3M. This fan has RPM monitoring, variable speed, with the sensor on a 12" lead.

For my fan I'd like to see a speed range from about 800-2000rpm, with the fan itself starting at max speed, then dropping back. I'd like to see an adjustment knob of some sort that allows the temp/rpm curve to be regulated.

If the fan was as quiet as a Yate Loon sleeve bearing model, at similar rpms, I'd be willing to pay a premium to get it. With a fan like this, you wouldn't need a separate controller, or Speedfan either. :lol:

Good luck building one.....

Oh yeah....I don't want to hear any PWM noises either (Globes handle PWM very well, Yate Loons don't)

Welcome to SPCR....build a better fan and the world will beat a path to your door (website). :)

StarfishChris
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Re: Build the perfect fan - tell us what you want

Post by StarfishChris » Wed Apr 13, 2005 3:47 pm

Though I wouldn't be able to buy at your site, here's what my perfect fan would be:

Preferred thickness (25.4mm or 38mm) - Some people don't have space for 38mm (e.g. if they changed a PSU fan or have a SFF) so I think 25mm is a must - though if a 38mm fan was significantly better I would rather have that (or a choice).
Fan material - doesn't matter as long as it isn't detrimental to performance/silence. Of course the fan shouldn't be too heavy as many like to decouple them from the case, so this probably removes metal from the equation (in 120mm only?)
Fan color or colors - doesn't matter, some clear fans are made of different plastics and resonate more so are less quiet.
Bearing type - Anything but ball-bearing as there can be some chatter and will get louder over time.
Constant or variable RPM - nice but not essential - there are inline leads available to reduce voltage, and fan speed controllers are easily available
Temperature control (Y/N) - I have no opinion (temperatures are at max constantly). Most people would rather stick the fan in, place the sensor in their heatsink and let the fan take care of the rest but I'm not fond of speeding up-slowing down
Sensor location/type - not on the fan itself if possible, this is not much use for case fans. A movable one is better. Type not important (IMO) as long as it works and we can stick it between heatsink fins
RPM signal output (Y/N) - again favouring performance over features, people like them but most of our quiet fans don't have them. It would still be welcomed, though.
Locked rotor alarm (Y/N) - not essential if there is RPM output - software can sense this and you can buy the alarms if you need it. I also think most SPCRers would rather have their computer shut down automatically than being woken up in the middle of the night :lol:
Autorestart (Y/N) - I wouldn't expect this feature & same response as above. Our typical computers aren't server grade, they won't be unattended for long periods of time, if software shuts down the PC it isn't such a big deal.
Power connector - Molex (with 3 pin connector for RPM sensing) as this allows the 7v/5v undervolting trick & can use the various commercial voltage reducing cables as well.
Lead length - 30cm, the lead needs to travel from back of case to the drives for their power. (I'm not sure how much you'd need exactly)
Lead wire colors or sleeving color - you can't go wrong with red/black (does anyone need a different colour to what comes out of their power supply?)
LED Yes/No - Most people here are against light pollution as well as noise (HTPC/ 24/7 running is the main reason why people want silence). I don't mind if they could be turned off but I would rather not have them at all.


I think Frank is correct in that Nexus fans are the price they are because they are consistent. If anything is going to challenge it then similar consistency is important - or they're cheap enough that you can get more than you need and pick the best, but I would rather have consistency.

yeha
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Re: Build the perfect fan - tell us what you want

Post by yeha » Wed Apr 13, 2005 5:51 pm

i'd just like to chime in with another duplicate response: the nexus fans are appreciated so much because the quality is constant. sure there are other popular fans, most of them much cheaper, but you have to buy several of them to find one that's suitably quiet. right now i have 20 or 30 80mm fans, none of which are as good as a single nexus would have been.

i'm not sure whether anyone knows how nexus performs their quality control - either they're buying fans as cheap as everyone else and cherry-picking in nexus headquarters, or they're paying the manufacturers more per fan for better qc at the manufacturing plant. whatever they do, that's what we're (happily) paying a premium for.

that said:

for all sizes:
- 25mm thick models are essential, but a 38mm-thick 120mm fan would be nice.
- fan material doesn't matter, so long as it isn't noise-inducing (vibrates, resonates, etc.)
- fan color or colors doesn't matter, it could be pink for all i care.
- bearing type shouldn't matter, but ball bearings get louder over time (right jafb2000?) - sleeve or hydrowave bearings would be better.
- rpm should be around 1400 for 80mm/92mm, and 1200 for 120mm. those won't be silent, but are all the headroom i would find acceptable.
- temperature control would only be useful for me if it was on/off like some nidec models - the fan is completely stopped until the thermistor reaches 55 degrees c or thereabouts, then it spins to full-speed. no ups-downs to worry about. thermistors should always be on the end of a lead.
- rpm signal output is useful for me, alarms and auto-restart are not.
- power connector should be dual 3-pin and 4-pin, so motherboard-based control is possible but 5-volt modding is also.
- lead length should be 18" or so, it can always be zip-tied later.
- lead colors or sleeving doesn't matter.
- led options, uv or other purely-cosmetic functions don't matter either. the only such addition i've liked has been the heavy extruded aluminum frame that some powmax fans come with - the frame does a good-enough job of vibration dampening that the fans can be hard-mounted with little noise.

now as for other non-standard features. the most important point of all would be quality control. it won't matter if your fan has the best specs in the world if it ticks, buzzes, clicks or makes grating noises - i don't know which link in the chain has to perform the quality checks but it has to be done, this is essential. otherwise it's just another quiet-ish fan, of which we already have many to choose from. also i guess the fact that it's going to be a low-rpm fan means that blade designs could be tweaked to improve air pressure and flow rate - perhaps once you're sub-800 rpm it becomes advantageous to use 16 or 20 blades, who knows. i certainly doubt that a particular set-in-stone blade design works best for all rpm ranges.

basically we want to move air and do it silently - some people shoot for 20 dba, others 15. start by finding fans capable of such a noise level free of any motor noise or vibration, and from those fans see what you can do to get the most airflow without making them any louder. once you've found the best air-pusher for those noise levels, put them up for sale :)

mathias
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Re: Build the perfect fan - tell us what you want

Post by mathias » Wed Apr 13, 2005 7:03 pm

For a 120:
Preferred thickness
- 38mm (though 50 would be even better), there are already many good 25mm thick options, but nothing any thicker. If it needs to be mounted on the outside of the case, so be it!
Bearing type
- sleeve bearings, really good ones
RPM
- 1100
Constant or variable RPM
- constant, unless it was bundled with a variable resistor on a 3-pin extension cord
Temperature control
- No
RPM signal output
- Yes
Locked rotor alarm
- No, but if instead it could activate a backup fan that would be nice
Power connector
- 3 pin, with a 3 to 4 pin adaptor with a resistor that brings the RPM down to ~700-900
LED
- No

Other special features
- Good undervoling capability, open corners

Elixer
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Post by Elixer » Wed Apr 13, 2005 7:21 pm

It would be good to see some larger case fans available for modding projects and power supplies. If someone could make a 140 and 160mm fans that were quiet, I'm sure they'd find a market.

el_
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Post by el_ » Wed Apr 13, 2005 7:27 pm

included isolated mounts like the directon kinda with two ends.


having a fan that starts at 5volts would be key too!

sleeved wires lead that is 12inchs long with pass thru would be nice.

autoboy
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Post by autoboy » Wed Apr 13, 2005 7:45 pm

Keep it simple. Adding LEDs and thermistors might not be wanted by every buyer.

Badger
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Post by Badger » Wed Apr 13, 2005 7:45 pm

I saw it mentioned before but I want to make sure it's emphasized:

No corners I have to saw through to use some rubber isolating screws like the Nexus 120mm!!!!!!!!!!!!!!!! Open corners are a must!

Thank you, it's neat that you're doing this.

Aleksi
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Post by Aleksi » Thu Apr 14, 2005 1:40 am

Hi guys,

first off, here's a text taken from SPCR's Links Section

fan users should consider before selecting a fan. Even though ball bearing fans appear to have longer life, they most likely will be noisier and cause far more complaints about noise that sleeve bearings fans. The point made here is that in those fan installations that have critical noise requirements, sleeve bearing fans will most likely meet the needs better than ball bearing fans.

There is one additional point to add and that is at low operating temperatures, sleeve bearings and ball bearings have similar life expectancies. At higher temperatures, sleeve bearings have a much lower life expectancy than the ball bearings.


I also live in europe, but here my 0.02€ on the matter: (who knows, maybe we'll arrange a group buy?)

120mm

Preferred thickness: 25.4mm
Fan material: (on a general level) I'd take plastic over metal
Fan color or colors: Doesn't really matter. Everything that is black, like black computers, are known to be faster and more efficient and generally just better. :)
Bearing type: Tough one. The main thing is quietness, second thing would be lifetime. So, sleeve bearing. (HWB would nice, but probably not possible?)
RPM: I'd need two speeds ~1000RPM and ~1600RPM. If I'd have to say only one speed, I think 1300RPM (like the orange Yate Loons) would be an interesting one.
Constant or variable RPM: Constant
Temperature control (Y/N): No thank you
Sensor location/type: ---
RPM signal output (Y/N): Yes please
Locked rotor alarm (Y/N): No thank you
Autorestart (Y/N): No thank you
Power connector: 3pin + 4pin.
Lead length: I think the 30cm would be enough
Lead wire colors or sleeving color: I prefer the black/red/orange over the coloring that Papst and Panaflo in some cases use (white/red/blue). No sleeving is necessary.
LED Yes/No: No thank you
LED locations/colors: ---

If possible, the use of Amphenol connectors (similar as Panaflos) would be extremely nice. However, these would up the cost a little.

Thanks for listening, your offer is appreciated here more than you know.

NeilBlanchard
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Post by NeilBlanchard » Thu Apr 14, 2005 2:15 am

Hello:

Smooth, no vibration, very quiet, 20-40CFM -- and OPEN CORNERS!

ckolivas
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Re: Build the perfect fan - tell us what you want

Post by ckolivas » Thu Apr 14, 2005 2:17 am

Bestbyteinc.com wrote:We are seeking input from hardcore silent PC fanatics about the ideal silent fan. Once we can reach some sort of consensus we will prototype the top selections, measure noise, choose packaging/labels, and submit for official review.
More than happy to provide!
*Most important: specify ideal RPM for each size
Compare Nexus fans 120mm@1000RPM, 92mm@1500RPM, 80mm@1500RPM
We usually need two ranges; low speed for ultra low flow applications, and medium speed for variable flow applications
Preferred thickness (25.4mm or 38mm)
25mm
Fan material
Fan color or colors
Don't care
Bearing type
Don't care as long as it's quiet
RPM
Somewhere in the 1000-2000 range
Constant or variable RPM
Temperature control (Y/N)
Sensor location/type
A choice of either constant or variable controlled by temperature
RPM signal output (Y/N)
Yes
Locked rotor alarm (Y/N)
No
Autorestart (Y/N)
Yes
Power connector
3 or 4 pin
Lead length
long; preferably at least 30cm
Lead wire colors or sleeving color
don't care
LED Yes/No
LED locations/colors
No

I think a serious oversight in this list are the two main things we're looking for that differentiate quiet good from quiet average. Regardless of the actual base speed of the fan, we look for the ability of the fan to run at significantly lower voltages than the default, to start at lower voltage or with pwm control and most importantly, to not buzz or click with lower voltage or pwm control.

To me the ultimate fan would be
Low speed for the size at 12v
Have a built in rpm sensor
Tolerate wide range of voltages and pwm control without clicking or buzzing (5-12v)
Optional - built in control to alter the voltage
Optional - a temperature controlled variable speed over a range of 40-60 degrees.

I'm very pleased to see someone try to provide what we want. Good luck!

Tiamat
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Post by Tiamat » Thu Apr 14, 2005 5:40 am

120mm
25.4mm thick
Sleeve
5V starting voltage
1200 rpm @ 12V
Open corners
RPM sensing
Motor: Never clicks, smooth, no chatter noise.

I think we should have a poll at the top of this thread. It will be much easier for bestbyteinc to collect the information. Just my 2 cents

burcakb
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Post by burcakb » Thu Apr 14, 2005 6:04 am

In addition to all the above:

as high a pressure curve as the fan can handle, preferably even when undervolted. I suppose this'll mean the fan will draw more current than usual so will have to use molex connectors. But of course i'd like an rpm output like the ones on PSUs (just the tach & ground signals on a 3-pin connector)

nici
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Post by nici » Thu Apr 14, 2005 6:33 am

Absolutely no ticking/clicking/chattering/grinding or other funny noises. I find those noises much more irritating than a airflow-woosh, and i dont like woosh either :lol: Thats what i love about nexus fans, they dont have any funny noises. All my Papst fans have motor/bearing noise that is clearly audible over the woosh at lower rpm, and thats where we are running our fans most of the time, low rpm. The same goes for a variety of other fans i have, even if the airflow noise id fine they click or tick. I wont use fans that have such incredibly irritating noises.

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Post by IsaacKuo » Thu Apr 14, 2005 7:47 am

I just want something very simple: a silent constant speed 80mm fan with 4 pin molex connector. That's it.

Preferred thickness: 25.4mm

Fan material: Ideally, some sort of rubber--but plastic is fine

Fan color or colors: Doesn't matter

Bearing type: Sleeve

RPM: Don't care as long as it's silent at standard voltage

Constant or variable RPM: Constant

Temperature control: No
Sensor location/type: None
RPM signal output: No
Locked rotor alarm: No

Autorestart: Not applicable

Power connector: 4 pin molex

Lead length: Doesn't matter. 6-12 inches is fine; I'll modify if it doesn't fit right.

Lead wire colors or sleeving color: Red/black

LED: No!

It might be interesting if the fan were made of soft rubber to provide its own vibration isolation.

Aleksi
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Post by Aleksi » Thu Apr 14, 2005 7:52 am

A bit off topic, but I think rubber manufacturing could cause some serious problems for the bearings. I'm thinking they wouldn't last too long, constant vibration or material softness could case some serious damage to the bearings. Or atleast that's my guess... :roll:

Tzupy
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Post by Tzupy » Thu Apr 14, 2005 9:56 am

Well, I'll tell about an idea of mine, not the desired fan specs: even the best 120 mm fan has a drawback. When used as a case fan, especially if on the side of the case, it lets noise escape. So my idea is to have a 'fan guard' that dampens noise, without impeding too much on the airflow. Something similar to the 'turbine' fan by Aerocool, but with fixed 'blades' that cover the whole outer area of the fan, made out of 2 mm thick sound absorbing materials. And some special dampener applied for the motor / bearings. Of course, that would require a case that has no fan guard itself, just the big holes. I think this concept would be especially useful for a case with two low-speed 120 mm back fans and the PSU moved towards the front and exhausting air through the right panel (another idea of mine).
I suppose this idea - if proved sound - may lead to patents, if so, please give me some credit for the original idea ;-)

frankgehry
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turbine fan

Post by frankgehry » Thu Apr 14, 2005 10:06 am

The turbine fan is about $3 worth of engineering and $15 worth of marketing. Maybe you could glue two 7 blade fans together and multiply 7*7 and get 49 times as much air flow. - FG

Only kidding.

OmegaZero
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Post by OmegaZero » Thu Apr 14, 2005 1:07 pm

While I realize that this is incredibly redundant at this point, I would like to stress again the importance of consistent quality from sample to sample.

Obviously lack of bearing/motor noise and lower audible turbulence are of the highest importance. I would suggest possibly adopting a similar blade design to the Panaflo OEM models in order to reduce turbulence - these models are currently my favorite for silence (in all sizes).

Also, many of us manually adjust voltages to suit specific needs from installation to installation. Because of this it is of added importance that fans start reliably at 5V, and that they ramp down smoothly in noise, RPM, and airflow.

Open-corner construction on the fan's frame is also a must. Most vibration dampening mounts and some heatsink mounts requite this.

For 120mm Fans

Preferred thickness: 25mm are essential, as they fit in all 120mm fan applications. 38mm are very useful when they fit. If we had to chose one, I would say the 25mm for sure - It would be nice to have both available though.

Fan material: Dense, Heavy, Stable Plastic.

Fan color or colors: Anything but clear or bright orange...

Bearing type: I am also not convinced that sleeve bearings are necessarily any quieter than a good quality ball bearing. I have found HIGH QUALITY ball bearings to be best, given their increased reliability. Panasonic's Hydro-Wave Sleeve bearings are a strong second though...

RPM: Given that I would be adjusting the voltage myself to suit specific installations, I would say about 2000RPM @ 12V would be fine as long as it is stable, quiet, and ramps down smoothly.

Constant or variable RPM: Constant

Temperature control: No

Sensor location/type: None

RPM signal output: Yes (RPM and ground wires on 3-pin connector if using a 4-pin MOLEX connector for power).

Locked rotor alarm: Yes

Auto-restart: Yes

Power connector: It would be nice to have both available - possibly like the interchangeable connectors on Panaflo fans.

Lead length: Again, having the option of longer or shorter lead would be nice. 20cm is a good standard length though, I think.

Lead wire colors or sleeving color: Red/black

LED: No. Especially not if it means having a clear plastic frame.


[EDIT] Added open-corner frame design notes and link to corner cutting guide.
Last edited by OmegaZero on Fri Apr 15, 2005 5:57 am, edited 4 times in total.

Voodoo Rufus
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Post by Voodoo Rufus » Thu Apr 14, 2005 1:18 pm

Same as the above poster, with preference to 38mm fans, blade shapes that are conducive to low noise, and rpms less than 2000.

Very low voltage operation of 3-4V capability is nice as well.

joshd2012
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Re: Build the perfect fan - tell us what you want

Post by joshd2012 » Thu Apr 14, 2005 3:41 pm

Bestbyteinc.com wrote: Preferred thickness (25.4mm or 38mm) - 25mm
Fan material - plastic
Fan color or colors - Black
Bearing type - Sleave
RPM - 1000
Constant or variable RPM - Constant
Temperature control (Y/N) - no
Sensor location/type
RPM signal output (Y/N) -yes
Locked rotor alarm (Y/N) - no
Autorestart (Y/N) - yes
Power connector - 3 pin
Lead length - longer the better
Lead wire colors or sleeving color - whatever
LED Yes/No - no
LED locations/colors

niels007
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Post by niels007 » Thu Apr 14, 2005 4:04 pm

for 120mm fans the Nexus (yate loon) is the best because it barely makes any motor noises, and barely makes any bearing noises. Extreme silent pc enthusiasts will never run it even at the low 1000rpm. Many are sub 700rpm. I use them at 500rpm max.

My point is, when used near 1000rpm, I can't see great improvements being made as this is mostly a 'wind woosh' sound that I don't think you can get rid off. CFM makes noise once it exceeds a certain amount on a given diameter fan.

However, I would like to see what the optimum fan design would be for a 120mm ~600rpm fan. What is the optimal amount of blades? What sort of a blade design is optimal for these low speeds? What bearings and motor absolotely do NOT vibrate or whirr /whine at these low speeds?

Honestly, the Nexus and low speed yate loon (I have both, they are 100% equal at the same rpm to me!) are pretty close to what seems achievable. For a cheap 120mm alternative a good source of low speed Yate Loon fans would serve most of us..

pony-tail
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Post by pony-tail » Thu Apr 14, 2005 11:54 pm

I generally use Panaflo fans -
I am happy with all but a few small issues.
They are NOT consistan from batch to batch
The ones with rpm monitoring are hard to get and make a ticking noise.
They do not handle back pressure as well as some other brands
They do not work well with PWM speed controllers.
All that said I still buy them (10 at a time) Pick out the Quietest and eBay the rest
Until a readily available , consistant , reasonably priced alternative comes along , that is as good as I can do here in Australia
I use 80x25 . 92x25 , 120x38 fans generally but a 120x25 would at times (where a 120x38 just does not have the clearance)be of use.
Colour is not important , leds NOT required , open corners a MUST, and nice Quiet smooth bearings of whatever type works best - CONSTANCY between samples is a NECESSITY
nominal rpms at 12v 1500 - 2000 but must be able to run at less than 1000 undervolted and start reliably at 5v and have rpm monitoring.
I forgot to add -: available in Australia

Bluefront
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Post by Bluefront » Fri Apr 15, 2005 3:18 am

Here's something to consider.....with the SFF market expanding, there is a growing need for small, thin, quiet computer fans. The selection of available fans of 50, 60 and 70mm with thin frames, and quiet running capibilities, is very limited.

Perhaps a forward-thinking company could develop a line of fans with the SFF community in mind. There is a definite need for some new thinking/design in this area. :)

OmegaZero
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Post by OmegaZero » Fri Apr 15, 2005 5:49 am

pony-tail wrote:open corners a MUST, and nice Quiet smooth bearings of whatever type works best - CONSTANCY between samples is a NECESSITY
YES! I forgot to mention the open corners - they are a must.

Again, consistent quality from sample to sample is also a must.

Shadowknight
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Post by Shadowknight » Sat Apr 16, 2005 10:12 am

I would like a QUIET fan that maximizes airflow, similar to YSTECH's Tip Magnetic Driving Fan II http://www.ystechusa.com/new_products.html
(As you can tell, going by the specs it's not very quiet)

Twill
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Post by Twill » Sat Apr 16, 2005 10:12 am

Bluefront, thank you...we SFFers need some quiet fans :)

60mm - sleeve bearing, plain black because they are going in PSUs usually or on NB heatsinks and so the bling bling factor will probably just cause problems/price increase. RPM monitoring is a must but variable controls would probably just get in the way. Thin in good.

They need a relatively high static pressure (is that right, means they can push against a lot of back pressure?) but they dont need HUGE airflow ~7-10 CFM would be ideal.

Need I say quiet/good undervolting? Yes, I think I will say that...needs to be quiet and have good ability to undervolt...probably on PWM.

Granted I'm about to put 2*120 Yate loon fans into a shuttle which will get rid of any need for other fans, but then, not many people want to try to get 240mm of fan into their SFF case.

I would ask for a 40mm version of this because that is what is standard on most SFF machines but I believe that would be asking a little TOO much now wouldn't it...but just imagine, a quiet chipset fan, oh the market for it! Even if it was loud, get rid of the whine!

/end rant

Thanks.

Twill

Shining Arcanine
Friend of SPCR
Posts: 502
Joined: Sat Oct 23, 2004 2:02 pm

Re: Build the perfect fan - tell us what you want

Post by Shining Arcanine » Sat Apr 16, 2005 10:53 am

The ideal silent fan would be a fan based off the (air moving) technology in the Ionic Breeze from Shaper Image:

http://www.sharperimage.com/us/en/catal ... NX/hppos=1

It would generate zero noise.

Since I doubt that is happening, here is what the next best fan would be:

Preferred thickness (25.4mm or 38mm)

I'm used to 25.4mm fans but it should be whatever allows the fan to give good CFM while generating the least noise.

Fan material

Doesn't matter as long as the fan doesn't exceed 150 grams and it doesn't hurt acoustics.

If there is a material can help acoustics (by lowering noise output/vibrations that translate into reasonance inside the case), then use it.

Fan color or colors

Every fan I've used was black but I really don't care so long as it isn't eye candy.

Bearing type

Whichever is quietest (least friction). Some examples would be Fluid Dynamic Bearings found in hard drives or HydroWave bearings found in Panaflo fans.

RPM

As low as possible (rounded up to the nearest hundred) as long as it maintains roughly 24CFM (so when I use an undervolted version to replace my Panaflo, I won't be giving up anything in terms of CFM).

Constant or variable RPM

Constant.

Temperature control (Y/N)

No.

Sensor location/type

Does this matter without temperature control?

RPM signal output (Y/N)

Yes but if it means more noise I could live without it.

Locked rotor alarm (Y/N)

Definately not.

Autorestart (Y/N)

Yes.

Power connector

Make it detactable and compatible with Panaflo fan cables. As for the default, it really doesn't matter if I can use my custom Panaflo fan cables.

Lead length

Whatever is standard.

Lead wire colors or sleeving color

Whatever is standard.

LED Yes/No

NO!

LED locations/colors

Without LEDs this shouldn't matter.

Other Features

Make it undervoltable so it can be run at 5 volts.

Make every effort to ensure it has the lowest noise output possible.

Open Corners.

Consistent Quality.

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