Did I get a bad batch of Gentle Typhoons?

[_Nickel_]

After waiting for them to become available in Germany for ages, I finally got some GT 1450s from outside Germany.

My problem is that even at 500 RPM they all still make a very noticeable bearing noise, causing them to not be inaudible from a distance of about 30cm/1ft. Other fans like my Noisblockers, Be Quiet USC, and even my Noctua and the Yate Loons are actually quieter, even though some them produce annoying ticking noises.
The bearing noise is unlike anything I've heard from other fans, it's mostly a relatively pleasant continous "hum" instead of the more irritating pulsing ticking noises that other fans tend to make.

What I wonder is whether anyone else can still hear the bearing very clearly at low RPMs or if I just got fans from bad batch and these fans are normally inaudible at ~500 RPM?

PS: At higher RPMs they're actually pretty good, the noise from the airflow turbulence is maybe the lowest I heard, and the bearing doesn't get that much noisier.

[b3nbranch]

I just put together a system with two Gentle Typhoon 1150 rpm in it. I have them slowed down with Zalman fanmates, but I don't know exactly how far because the motherboard is reporting ridiculous numbers (such as 6,000 rpm for an 1150 rpm fan).

I can hear the bearing hum, but only if nothing else is going on in the room. Right now I can hear it because a) my wife's computer is turned off, and b) you've drawn my attention towards it. The hum is inoffensive, and I often forget about it. In the summer I will see exactly how low I can go on the rpm, but I still expect some of the gentle hum.

[_Nickel_]

Yeah, the noise they make is quite "inoffensive" compared to the noise that most other fans make.

But mine are definitely not inadubile at low RPMs.

Are you using them on the lowest setting of the fan mate?

[b3nbranch]

Yeah, the noise they make is quite "inoffensive" compared to the noise that most other fans make.

But mine are definitely not inadubile at low RPMs.

Are you using them on the lowest setting of the fan mate?

No, I would estimate I am using them at about 60% setting. I could go lower during this time of year, when the room temperature is about 20-21C, but I may want them this high during the summer. I'll do a stress test this summer and find the lowest setting I can safely use. I think the hum will still be there, just maybe a little softer if Igo down to 50% or 40%.

[Compddd]

I have my GT 1450RPM at 60% on a Zalman fanmate inside a Silverstone FT02 with all other fans at 5V and I can't hear it. I can hear it if I use the fanmate to dial in certain RPMs, I had to find the sweet spot.

[ces]

No, I would estimate I am using them at about 60% setting. I could go lower during this time of year, when the room temperature is about 20-21C, but I may want them this high during the summer. I'll do a stress test this summer and find the lowest setting I can safely use. I think the hum will still be there, just maybe a little softer if Igo down to 50% or 40%.

I have heard that if you run them at speeds other than their 12 volt speed, they can have unwanted resonances.

[ces]

Other fans like my Noisblockers, Be Quiet USC, and even my Noctua and the Yate Loons are actually quieter,

Does that mean that you find the Noiseblockers and Be Quiet fans to be one notch above the Noctua fans?

Is that a common assessment in Europe where the Noiseblockers and Be Quiet fans are more available than in the US?

How would you compare the Noiseblockers to the Noctua fans?

[b3nbranch]

No, I would estimate I am using them at about 60% setting. I could go lower during this time of year, when the room temperature is about 20-21C, but I may want them this high during the summer. I'll do a stress test this summer and find the lowest setting I can safely use. I think the hum will still be there, just maybe a little softer if Igo down to 50% or 40%.

I have heard that if you run them at speeds other than their 12 volt speed, they can have unwanted resonances.

They are definitely louder at 12 volts than when dialed down with the fanmates. Perhaps there can be some resonances but they should be
avoidable by changing the RPM a little bit.

Come summer I intend to see how low I can go with the RPMs, right now it's running pretty cool.

[gcwebbyuk]

I have a pair of 1650s running at about 990rpm. They are the loudest part of my system now

I run 2 SFF21Es and a Kaze Slim 1200 - all running at between 660 rpm and 1000 rpm and the GTs are noiser. It sounds like a motor noise rather than a wind noise, and you can definately hear the motor kick in if you turn up the speed.

Are they better mounted horizontally or vertically, as I may swap them around in the case. At the moment they are mounted as the front intake and rear exhaust.