Eliminating resonance from your case.

[Bluefront]

I've been getting resonance from my case.....caused by the fans. Their speeds vary depending on temps. At certain rpms, I was getting a resonance sound......very annoying. Here's what I did that seems to be working...

From an auto parts store, I bought a package of stick-on wheel weights, made for mag wheels. The type I got come in strips about 8" long, about 3oz total. I wrapped the case fans with these strips, using two strips per fan. Seems to have worked....and I haven't heard the noise since the weights were applied. I guess you could apply the weights on other parts that might vibrate, such as a noisy cdrom....

 

[SuperPickle]

Resonance sucks. I had some issues with my full-tower too. I found a roll of ¼"rubber sheeting from Firestone--I think it's used for roof repair. Using spray glue, I lined the sides of my case with the sheeting and it cut the noise a bunch but it also made my case more heavierest. Getting rid of the hum was worth it.

Those weights cheap?

 

[OulOat]

You sure having magnets around sensitive data storage devices is a good idea?

 

[Sporko]

They're just lead weights, not magnets.

 

[OulOat]

My bad then, I read the mag wheels and thought it was magnetized

 

[Bluefront]

They're very cheap. If you wanted to save money you could probably get all the free wheel weights you wanted from a store that balances wheels.....they usually disgard the old weights. Course these ones I used are better suited to computer use. They come in flexable strips with a sticky foam backing.

A magnitized piece of lead?....heh.

 

[Lash444]

Don't know if this is a good or bad idea...but with my old case I used extremely thin styrofoam between the case and the fans. I had mounted the fans directly to the case in a mod and was getting some resonance from that. It took care of my problem with resonance but due to the enormous amount of airflow that was being pumped i still had that *whoosh * sound from so much air being pumped. Good luck.

Nick

 

[Smilin]

I had a bit of trouble with a 'standing wave' from my blowhole fan. One day I picked up a copy of Myst III collectors edition (for $19.95!) from the store. It had this little metal figurine that came with it. Out of curiosity I set it on top of my case. If in the right spot the couple ounces of weight make the sound completely stop. Yay.

 

[InverseOfNeo]

Thanks! I might have to do that!

 

[jodhas]

This will surely help.

 

[Lizardman]

I just got finished taking my Vibrations and controls class for my mech eng BS. That class sucked big time. I am just mentioning this because we this is the kinda of stuff we learned how to compute. ie when will an object vibrate when a force is applied to it.

 

[Bluefront]

There's a difference from just plain noise....like a sound airflow makes, or a bearing noise from a fast hard drive......and a resonance noise. I can't explain it except to say, when you hear it, you'll know what I'm talking about. And it's not a vibration noise.

In the case of my resonance noise, it was an acoustic interaction which happened when my three fans ran at certain speeds....different speeds for each. They were not vibrating at all (far as I could tell anyway). Adding the weight of the lead strips somehow affected the occurance of the resonance. I've had no book learning on this subject, but I've learned about it over the years. This is the first computer I've built that has had this problem. hopefully it's fixed....