Were does my noise come from?

HeadCrusher

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Mar 20, 2002
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Along with the Firepod I finally got some real monitors. Unfortunetally they're making strange noises while the computer is turned on. When I play back a mix the noise is overpowered by the music but without any playback it's kinda anoying. They are positioned right next to my notebook but the specs say they are shielded...
Any ideas?
 
Sounds like a ground loop or 60 cycle hum. Does it go away when the notebook is powered by the battery only? if so, that's the likely problem.
 
I get high pitched whining noise through my monitors when my CPU is under load. My PCs PSU seems to dirty up the power (for instance my tv has fuzzy lines across it when the PC is on) but since I'm only on 1-phase here at home, I can't seem to escape it, haha.
 
Sounds like a ground loop or 60 cycle hum. Does it go away when the notebook is powered by the battery only? if so, that's the likely problem.
Gonna try that tomorrow, thanks for the input.
If that's it how am I gonna solve the problem?

No HP devices in the whole house so that's probably not it.
 
You can buy small ground loop "breaker" boxes from electronic stores. A lot of people have problems with ground loops with home cinema systems so a high-end audio store should have one. I had a ground loop problem when I had a laptop-based DAW and got one of those and it fixed the problem.

I guess you could also try switching the plugs on the adapter for the notebook or the monitors first. It could be the connectors in the plugs causing the problem. Unfortunately, I'm no electronics expert though.

In Europe I think it's called 50 cycle hum and not 60 cycle like it is in the US. It's bloody irritating though!.
 
In Europe AC power is 50 cycle, in the US it's 60 cycle. In either case, if it's low, monotonous, and goes away when you touch something metal on the monitor (a part of metal on the monitor, not poking the monitor randomly with a paper clip), it's ground loop. If it's hissy, crackly, or has noticeable variance, it's probably not ground loop and there could be some other form of interference.

Since you mentioned it coming in when your computer was on, move the monitors away from the notebook and see if anything changes. If that doesn't help, get a breaker box or plug the monitors and notebook in to different outlets. If neither of those change anything, we'll need more details.

EDIT: Misread, small change. END EDIT

Jeff
 
Ok, tried powering it with the battery only: Noise went away! There is still something I can hear when I stick my ears right in front of the speaker but I guess that could be the noise from the poweramp of the speakers, could it?

I tried plugging the notebook power supply into different outlets - didn't help. I'll experiment with some more different combinations today.

Moving the monitors didn't change anything - they couldn't be moved far anyway...

What about the cables from the FirePod to the monitors? Could they be making problems?

Thanks for all the help so far!
 
Break the ground pins off the power cables to your monitors. I'm almost positive your having ground issue i had the same thing and its just caused from a bunch of things pulling from one ground aka computer and monitors and anything else for that mater thats hooked up. I broke my ground pins off and no more computer noise in my monitors. I was having exact same problem you seem to explain!!

Good luck hope that works:rock:
 
Don't break anything off of power cables. You can buy ground lifters from any electronics store for less than a dollar.

How do you have your monitors connected?
 
I would also recommend against breaking off parts of the power cable, as I've seen cases where that's been enough to cause permanent disability to part of a hand when plugged in. It's far cheaper in the long run to just avoid the risk and get a ground lifter.

If jiggling the connections, or touching the plugs, to the monitors doesn't help then cables aren't the big issue.

Jeff
 
Well, I guess I won't rather break anything of my cables. Might work but that's a bit to risky for me (for warranty and safety issues).

No, touching cables or monitors doesn't help. So I guess I'll have to look out for a ground lifter. Just don't know what they are called in German in order to buy them here... :lol:
But I'll guess I'll find a shop that knows. ;) From what I found of Google they are small plugs to be inserted between the cable and the monitor, right?

As for cables: Never really understood what the difference between normal 1/4 and balanced was... Can someone explain please?
The guy at the shop were I bought the monitors said I could use normal guitar (instrument) cables so I went with that...
XLR is out of question as the FirePod only hast 1/4 outs.
 
well my power cables are the interchangeable 3 pin ones that are on everything like computers and rack gear ext... If there cables like that there cheap to buy and i got like 100 of them so i broke ground pins off 2 of them and I'm good to go!! I guess if there hard wired then yea don't break off buy the ground lift adapter thing!!
 
I think so. Never listen to "guys at the shop". :) I have trouble telling which kind of cable to use myself all the time though. I have to take it on a case by case basis.