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 Post subject: Anyone try Elastomeric Fan Isolators from Silicon Acoustics?
PostPosted: Sun Sep 22, 2002 6:16 pm 
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Joined: Sun Aug 11, 2002 3:26 pm
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Location: Philadelphia, PA, USA
Read about them here at Silicon Acoustics, and from the manufacturer, Ear Specialty Composites, here.

I must say that I'm a little incredulous as to their claims of 7dB noise reduction. I mean, that's staggering. I imagine those kinds of numbers are only possible when much of the noise generated is from vibrations being transferred to the case rather than air noise. I wonder what kind of effect they would have coupled to low speed Panaflos or Papsts?

Also, the manufacturer website indicates that they also make grommets for mounting harddrives. Again, they claim the grommets produce a 7db reduction from idle or seek. How can these numbers possibly be true? Silicon Acoustics doesn't sell theses hard drive grommets, so I have no idea how you would purchase them even if it were true.

I e-mailed back and forth with the manufacturer a month or two ago trying to find another retailer for these, or some independent review, but I never heard anything back from the sales rep they put me in contact with.

Anyway, if these things are capable of producing any kind of significant (even 2-3db) noise reduction, I'm sure tons of us here on SPCR would love to have them. So, does anyone have any experience with them? Any chance MikeC can get some review samples?


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PostPosted: Sun Sep 22, 2002 7:53 pm 
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Location: Vancouver, BC, Canada
I have some samples from SA, and no I have never tried to measure, but yes, they can make quite a big difference if you have a fan with lots of vibration -- like many high speed fans. There is an improvement with Panaflos, maybe 3-4 dB at 12V. It is VERY dependent on your particular case, position, fan, etc. Generally, mechanical decoupling has about the biggest influence in total system noise output. Try them.

BTW, thank for the link to http://www.earsc.com/ -- interesting stuff!

I do think a 7 dBA improvement is possible if you have a particular resonant case and a HDD with lots of vibes. Seagate confirms that mounting methods matter more in final system noise than the airborne noise of the drive. (see our recommended HDD pages for more.)


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 Post subject: Re: Anyone try Elastomeric Fan Isolators from Silicon Acoust
PostPosted: Wed Sep 25, 2002 10:47 pm 
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Hmmm... Interesting. I wonder if anyone's tried to use these on their power supply fan. In most cases, there's not a whole lot of room between the case and the PS, I would probably have to drill holes in the case to give the Isolator heads enough room to fit.


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 Post subject:
PostPosted: Thu Sep 26, 2002 1:11 pm 
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Location: Santa Clara, CA
grommets provide little benifit for low-rpm well-balanced fans but can provide substantial benifit for high-rpm or poorly-balanced fans and can be amplified by the resonance frequeny of your case setup. in the later situation especially, i don't doubt SA's claims. if your case is already on the road to silence, don't expect grommets to provide those type of noise reductions, though.

for hard drives, grommits really helps in dampen seek noise and decoupling the high frequency resonant noise your case may amplify. again, SA's claim is not absurb in this manner, either. howver, grommets have no effect for airborn noises the drive may produce.

for the power supply, if you're willing to open it up already, you may want to try replacing the generic fan with a an undervolted low-speed well-balanced fan as this will probably make a larger difference than trying to silence the vibrations from a high-speed unbalanced fan.

by the way, you can pick up generic grommits at many local electronics store, like radio shack, fry's, etc.


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 Post subject:
PostPosted: Thu Sep 26, 2002 3:55 pm 
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Location: Worcester, UK
Yeah, grommets are just standard items, i paid £0.40 for 10 tho i think they got the price wrong, it should have been £0.40 for 4.


Edit: Should have said the 'standard grommets' i refered to are the 'H' profile ones Mike mentioned below. I think they're normally used to protect cables passing through sheet metal. Dont think the SA ones are available in the UK, but like others i found that the standard ones dont make much difference to low RPM fans.

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Last edited by ChiefWeasel on Fri Sep 27, 2002 3:20 am, edited 1 time in total.

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 Post subject:
PostPosted: Thu Sep 26, 2002 4:06 pm 
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Having spent way too much time messing with grommets, I have to say there are significant differences. Many are made of fairly hard rubber and still transmit some mech. vibes. The softer ones work better, and it can be a pain looking for the right size and softness along with the "H" profile grommet (double-flange?) you need to get real decoupling with screws. The fan grommet samples from SA are soft & stretchy and do provide better damping than the typical grommet. I agree about low speed fans not making enough vibes to make decouple-mounting a must.


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 Post subject:
PostPosted: Thu Sep 26, 2002 6:08 pm 
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Location: Philadelphia, PA, USA
Yeah, I've tried "regular" grommets from electronics stores, but I haven't found them very effective. I wound up using them more as spacers to keep fan blades away from sheet metal then as vibration dampeners. And while I'm happy to drill additional holes for mounting fans, case handles, or whatever, I'm less enthusiastic about modding the hard drive mounting "slots" to accomodate grommets that don't seem to work so hot anyway.


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