New rheobus and panaflos... AWFUL noise!

[beatle]

I went from 4 L1a's and an H1a on my cpu to all H1a fans. The case is a Coolermaster 201C-SX2. I also put in one of those 3.5" rheobuses from SVC to cut them back when I don't need all the flow. After wrestling the last fan (blowhole) into the case I turned it on. It sounded like it was dying! After determining that the blowhole was the worst of all of them I unplugged it. The rest of the fans have this bad whirring noise that reminds me of a ball bearing harddrive that's out of warranty. This problem is made worse if I turn the fans down. Is this common? Bad rheobus? Bad design? Bad fans? This isn't what I was expecting at all...

 

[BG4533]

The H1As aren't quite as good as the other Panaflos. At their stock voltage their noise level is decent for the air they flow, but they have a slightly off sound. At 5-7V they don't flow the best air and the off sound is either worse or more apparent becuase of the lack of air noise. The only experience I have had with them is the ones I bought at MPJA. Your rheobus could be making the problem worse or you may have gotten really bad ones because mine didn't sound like they were dying. Basically, decent fan at 12V, bad at 5-7V. I originally purchased these and a Sunbeam rheobus as upgrades to my NMBs, but I decided to use 80mm and 92mm L1As as well. If you have the ability to mod your case to fit the 92mm L1As I would reccomend that. They are very quiet at 7V and still flow decent air.

 

[beatle]

Hmm, I had no idea the H1a's were that much worse than the L1a and M1a (which I also used.) I thought that the rheobus itself would make noise if it were junk, not make the fans noisy. I also bought my fans from MPJA, FWIW.

 

[BG4533]

I have heard about certain rheobuses making fans sound worse, but it is likely just the fans. How do the fans sound when they are plugged in without the rheobus? Some people like the M1As on a rheobus.

Brian

 

[beatle]

It sounded about the same when plugged into the mb header, which isn't too bad, considering it's blowing 39cfm. It really rears its ugly head when turned down. It's a shame, because I only picked up the rheobus and these fans so I could turn these fans UP when it gets hot this summer and I'm loading up the cpu.

 

[Blooz1]

Interesting....I've got 4 H1A's in my Lian-Li case, and 3 more in my other system. NONE of them make any noises like you described! I also bought them at MPJA, and both systems are set up with Sunbeam rheobuses.

The Lian-Li system runs 24/7, and is virtually silent when the fans are turned down to 50%. Both systems sit in my living room, so I'm sure I'd notice any unusual noises!

 

[beatle]

I'm wondering if the rheobus is to blame somehow. I wish I had a microphone to record this awful noise. I'm going to try plugging in some of my L1a's and my M1a to see if they make noise when turned down.

EDIT: Maybe its because this rheobus uses pulse width modulation to control the fans and not voltage regulation. Possible? I also notice that I appear to have v2.0 of this rheobus. My knobs are squared off spun aluminum and not rounded like I see on so many sites. Seen here at Jab-Tech.

 

[scdill]

beatle, supposedly having an air imbalance can cause fan noise. Have you tried different combinations of fans blowing in and out? Realizing it worked before, but still maybe with the different amounts of air being moved by the H1a's ...

 

[beatle]

I think this is a little too dramatic to be chalked up to air imbalance. I've tried many different combinations of certain fans up or down and its always the same problem with the ones that are turned down from full power.

 

[cpufan]

I have a Vantec rheobus that exhibits the same behavior. No matter what fans are plugged in, when the unit is turned down, it eminates a buzzing noise (for lack of a better description). In my case, the noise is definetly the rheobus, and I suspect it is the same for you. Have you tried other fans? I have tried many. The Rheobus can not quietly output a reduced voltage for some reason.

Put your ear by the rheobus- I'm almost certain that it is your problem. Now if I only knew how to fix it...

 

[RalfHutter]

Originally posted by: beatle
I'm wondering if the rheobus is to blame somehow. I wish I had a microphone to record this awful noise. I'm going to try plugging in some of my L1a's and my M1a to see if they make noise when turned down.

EDIT: Maybe its because this rheobus uses pulse width modulation to control the fans and not voltage regulation. Possible? I also notice that I appear to have v2.0 of this rheobus. My knobs are squared off spun aluminum and not rounded like I see on so many sites. Seen here at Jab-Tech.

Is this the reobus you got from SVC?

"3.5" Drive Bay VR Fan Speed Controller - Black

Specifications:
- 4 channel outputs
- 8 Watts per channel
- 12V+/- 10% DC input
- 7~12V+/- 10% DC output
- pulse width modulation"

If so, your problem is the PWM. This makes an awful racket as you turn the speed down. It gets worse and worse the more you turn the speed down. These types of rheobuses are worthless for a low noise solution. The ones to get from SVC are the Sunbeam or the Zalman ZM-MFC1.

 

[beatle]

Yup, that's the one. I suppose it could be the rheobus. Now that I take my ear to each fan, the noise seems more and more omnidirectional. I'll give SVC a call today and give the sunbeam a try (doh, they're out of stock.)

I knew that PWM rheobuses made a faint "clicking" noise when turned all the way down, but a lot of people said it was not intrusive. This is really awful, to the point where it only makes the entire system louder.

 

[deerslayer]

Originally posted by: cpufan
I have a Vantec rheobus that exhibits the same behavior. No matter what fans are plugged in, when the unit is turned down, it eminates a buzzing noise (for lack of a better description). In my case, the noise is definetly the rheobus, and I suspect it is the same for you. Have you tried other fans? I have tried many. The Rheobus can not quietly output a reduced voltage for some reason.

Put your ear by the rheobus- I'm almost certain that it is your problem. Now if I only knew how to fix it...

This is a common problem with the Vantec rheobuses

 

[beatle]

A friend of mine with a Vantec rheobus says he only has problems when it is turned down all the way and it's not really loud. He said some fans don't like being turned down. This is news to me, as I thought the only problem you might have would be stalling. Putting my ear to the front of the rheobus reveals nothing. It seems to be coming from everywhere...

UPDATE: It's the fans! I took one of the H1a's out of the case and turned it on with the rheobus. It has this clicking noise that is very apparent. As a blowhole resonating through the case I can see why it made such a racket. My M1a doesn't make this clicking noise when turned down and neither does my brother's ultra high speed Sunon. The H1a is apparently a great fan if you're not going to turn it down, but forget about it if you are.

 

[0roo0roo]

yup, my cheapo led fans from svc don't make a peep with a pwm rheobus. stealth fans who make a slight click to begin with don't get any louder. my sunon doensn't either. slight buzz from rheobus but only if your head is inches from the thing.

 

[beatle]

I take that back about the M1a. I also found out that the L1a buzzes! It's all Sunon now.

 

[Zepper]

The bearing in the Panaflow is a special design sleeve bearing that dynamically centers when it attains a certain speed - any lower and you get noise.
. So for quiet operation with rheobus et al. use ball-bearing fans (preferably dual ball-bearing)...
.bh.
Hoping for some :sun:!

 

[BG4533]

Originally posted by: beatle
I take that back about the M1a. I also found out that the L1a buzzes! It's all Sunon now.

I just set up a system of 80mm and 92mm L1As hooked to a Sunbeam Rheobus. 3-92mm case fans, 2-80mm case fans, and 1 80mm and 1 92mm L1A in my Truepower. None of these fans really buzz at any voltage. They make a very slight ticking at 5V, but it is only audible with my ear 4" from the fans. I havent had a good chance to fully test what this can do, but with the fans all the way up my MB temperature=ambient and with them down to 5V I get good cooling and a silent computer.

Brian

 

[beatle]

It could be that panaflos just don't like to have their pulse width modulated. The Sunons, while not as "smooth" sounding as the panaflos at full speed, give me more flexibility in how much air I want to put through the case, which is ideal for when I go to a LAN and the room temperature is over 80 degrees.

 

[Jhhnn]

Panaflos and pwm don't mix well, that's all there is to it. If you run one of those H1A's at 7v, it'll be nice and quiet.... the same bearings are used in all the 80mm panaflos, at different rpm's...