Humming without the computer

[F]bernZ · Post by **[F]bernZ** » Sun Feb 04, 2007 10:30 pm

Well.. I've got a good idea on what may be going on, but I wanted to ask you guys.

As of right now, my WD2500KS is sitting on a piece of foam which is easily compressed. However, I am still getting some extremely disturbing humming sounds.

I proceeded to turn my computer OFF.. and I found that even with the computer off, the humming is still present!

My computer is located in a location where it has immediate 4 sided boundaries - top, behind, right, bottom, and the front, somewhat.

Although it looks quite open (the area that is), I believe that this area is actually picking up more ambient vibrations from the entire house. My question is, would an area like this be able to pick up sufficient vibration and actually hum?

Attached is a picture of the area..
http://img79.imageshack.us/my.php?image=dsc00147as4.jpg

DeltaForce · Post by **DeltaForce** » Sun Feb 04, 2007 11:46 pm

Try unplugging the powersupply cord from the wall, and see if it stops. Try moving the computer, opening the case door and listening, etc. How thin are the panels; are they resonating? You should be able to solve it through trial and error.

[F]bernZ · Post by **[F]bernZ** » Sun Feb 04, 2007 11:55 pm

Well, the point, there shouldn't be any energy in the area enough to cause my case itself to vibrate. I was just wondering where the humming sound is coming from, since I've even gone as far as to removing the computer itself from the area and I'm still getting the hum.

While the panels aren't the thickest, they're not resonating.

jaganath · Post by **jaganath** » Sun Feb 04, 2007 11:58 pm

I've even gone as far as to removing the computer itself from the area and I'm still getting the hum.

Well that completely rules out the computer, it might be caused by your speakers or AC/DC brick for your LCD.

DeltaForce · Post by **DeltaForce** » Mon Feb 05, 2007 12:02 am

Do you hear the humming all the time? If so, you might have tinnitus without realizing it. I have tinnitus.

DeltaForce · Post by **DeltaForce** » Mon Feb 05, 2007 12:05 am

Also, did you unplug from the wall every power component to see what happens? Try turning off the lights -some hum.

[F]bernZ · Post by **[F]bernZ** » Mon Feb 05, 2007 1:12 am

Its definitely not the lights or the AC/DC brick.

If I just pull my head out of that 'cave' area, the humming disappears immediately. As it stands right now, with my head just under 1m, I can hear the humming. If I stand up, it goes away.

If I duck down underneath the table, it also goes away.
I'm pretty sure its just something to do with that AREA of the room, where ambient noise just seems to get amplified.

Edit: And since I can't hear it when I stand up, I'll assume I don't have tinnitus ? What is it anyway?

jaganath · Post by **jaganath** » Mon Feb 05, 2007 2:16 am

It's probably amplifying the hum from another device, like the compressor on a fridge somewhere in the house. I've had that happen before. Tinnitus is a medical condition, constant ringing in the ears.

DanW · Post by **DanW** » Mon Feb 05, 2007 4:28 am

what about that shelf above your PC? Is that vibrating?

try clearing the area of everything, if it goes away try replacing everything slowly and see what it is.

Like bernz said, it could be a AC/DC power brick, my surround speakers make a really anoying buzz only really noticable when the PC is off. But I would notice it all the time if I the PC was quieter.

[F]bernZ · Post by **[F]bernZ** » Mon Feb 05, 2007 7:29 am

Nuh uh. Shelf above the PC is definitely not vibrating.

If I removed the shelf above the PC, do you think it'll get rid of the amplification qualities of the area? I'm buying into Jaganath's explanation because it makes much more sense to me.

CoolGav · Post by **CoolGav** » Mon Feb 05, 2007 7:57 am

You could acoustically treat that part of the room with a simple trap or panel. I'm guessing the hum isn't that low in frequency, which means hangin some foam or a pillow might damp it enough so it's no longer heard.

[F]bernZ · Post by **[F]bernZ** » Mon Feb 05, 2007 8:38 pm

Actually, the hum is quite low in frequency. I'd say somewhere in about the 80Hz range? Its certainly lower than the hum my HDD used to emit when I hard mounted it into my case.

jaganath · Post by **jaganath** » Tue Feb 06, 2007 2:21 am

did you try removing the shelf? My gut feeling is that it won't solve the problem, but you never know.

Post by **CA_Steve** » Tue Feb 06, 2007 6:52 am

As mentioned, it might be a sympathetic resonance with another device elsewhere in the building...

A couple of possible sources (and my current bane):
- gas furnace hum
- compressor hum from your refrigerator

Tracking down low frequency sources can be a pain as they don't need to be direct/line-of-sight to propagate around your house (eg: sub-woofer)

[F]bernZ · Post by **[F]bernZ** » Tue Feb 06, 2007 9:39 am

Nah, I haven't tried removing the shelf yet. I do believe its the house furnace going, because it tends to hum when the heat comes on.

Ah well, the Corsair 520HX and an elastic suspension works wonders for cases. =)