Need a hand identifying an EMI/noise issue

I doubt it's the actual shape of the waveform that's the problem. You are picking it up via your guitar. That means that you have a magnetic field (pickups sense magnetic fields). What causes a magnetic field is a current loop. Normally you don't get much loop area since the hot and return run next to each other. However, if the current isn't returning correctly, you will get a huge loop area which will cause a large magnetic field (and sterilize you).

So this means you have a wiring problem. You really need an electrician to look at it.

P.S. joking about the sterilize part.
 
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I've got almost the exact same noise as you, as a matter of fact you could have told me you were in my house and I'd believe you. I can find a sweet spot where it's not horrible, but it's a pretty slim area to make sure I'm facing all the time. I thought that it was power related for a while, but it seems like most of the energy are on the harmonics rather than at 60Hz. I kind of just deal with it these days and have come to accept that even with noise cancelling pickups or humbuckers that I'm going to get some noise a lot of times.
 
FractalAudio said:
I doubt it's the actual shape of the waveform that's the problem. You are picking it up via your guitar. That means that you have a magnetic field (pickups sense magnetic fields). What causes a magnetic field is a current loop. Normally you don't get much loop area since the hot and return run next to each other. However, if the current isn't returning correctly, you will get a huge loop area which will cause a large magnetic field (and sterilize you).

So this means you have a wiring problem. You really need an electrician to look at it.

P.S. joking about the sterilize part.
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I have the usual sub-hundred-bucks wiring checkers from Home depot, and they all say that my voltage is good and that my outlets don't have an issue. You happen to know a good electrician in this area that would be able to troubleshoot this? I think my usual guy would just say "lights are on, it must be working".

If this will really sterilize me, I'll need a heads up. Kids are expensive and I need another Axe-Fx, so I'll be holding my junk up to the outlets for the next few days...

:D
 
Quick question, what voltage do you get on your ground pins when you plug in? Also, did you try taking off the breakers like I suggested on the first page? I suspect the main culprit would be easy to find, and proper grounding would take care of the rest if you DO have a dirty ground.
 
MG-Chris said:
I have the usual sub-hundred-bucks wiring checkers from Home depot, and they all say that my voltage is good and that my outlets don't have an issue. You happen to know a good electrician in this area that would be able to troubleshoot this? I think my usual guy would just say "lights are on, it must be working".

If this will really sterilize me, I'll need a heads up. Kids are expensive and I need another Axe-Fx, so I'll be holding my junk up to the outlets for the next few days...

:D
Click to expand...

An outlet checker is useless for this.

Also, the grounding could just be bad. The whole thing about it going away when it rained points to a grounding issue. When it rains, the ground improves. A quick test is to run a heavy wire from the panel ground to a nearby cold water pipe (if they are copper).

Or as Jon stated, it could be a dirty ground. There should never be any current flowing in the ground wire. It is for safety only. But sometimes an electrician hooks up the wrong wires to something and current flows in the ground. Another cause is leakage. Faulty equipment can leak current into the ground. Even properly functioning equipment can leak some current. Due to finite resistance, the ground will now have a voltage on it. Anything on that branch will bounce with the voltage. Tough to find though since you can't measure the voltage on the ground without running a wire to a known zero potential.

I'm not an expert in residential wiring. You really should find a good electrician. I don't know any.
 
I normally reference to water lines (unpainted of course) if I'm trying to track a ground problem. Not always the best, but it gives a quick (and usually good) reference. Also +1 for equipment leaking to ground, I get that kind of problem all the time at work, both low voltage and high voltage. Very pronounced with high voltage.
 
FractalAudio said:
There should never be any current flowing in the ground wire. It is for safety only. But sometimes an electrician hooks up the wrong wires to something and current flows in the ground. Another cause is leakage. Faulty equipment can leak current into the ground.
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Not only that, but AFAIK also:
Amazon.com: Electrocution of America: Is Your Utility Company Out to Kill You? (9780977968503): Russ Allen: Books
Amazon.com: The Great Power-Line Cover-Up: How the Utilities and the Government Are Trying to Hide the Cancer Hazard Posed by Electromagnetic Fields (9780316109116): Paul Brodeur: Books

In short, I read from a knowledgeable guy in Holland: "In the USA 70% of this neutral power goes back to the powerstation, not by cables, but through the ground. That way you may have a lot of stray currents, which a grounding rod may pick up, and bring those unwantedly back into the house."
I believe with the "70%" he means it's done like that in most states, but I'm not sure [see books].

That's another reason why the Earthing - Connect to the Earth and feel better...fast! hype that's been going on in the last few years in alternative medicine is not recommended with the tools they're selling, esp. in America. I've heard from people using these tools, there can indeed be a lot of voltage[?] on their ground wire, so it makes you worse off!
If the ground is good, it probably *is* very healthy to ground barefoot, but I wouldn't use those tools myself (have them, don't trust it or feel better with them).
 
Another quick question, did you also switch the ground switch off? What were the results?

I also have a pretty high noise gate threshold too....can't remember how much offhand, I do it for each patch by ear till I get what I want, and set and forget it.
 
Maybe you've been down this path already, but when I've had local interference to track down, it's pretty much always turned out to be a single piece of equipment that I've tracked down by turning things off until the noise went away. You can start by switching off entire circuits at the breaker panel. If you can narrow it down to a single circuit, you can start unplugging things to find the culprit.
 
Unfortunately, this is simply the state of things today. There is so much EMF/RF/Microwave/etc pollution in the air/ground, I'm not sure one can ever be free from it's effects. There's at least one forum member here from Alaska... I wonder if he/she would have anything to say about the HAARP installation and it's local effects?
 
Just updating this, since I know people are clearly losing sleep over it.

I just had two electricians here, and the foreman said "This is the weirdest thing I've seen in 35 years of doing this".

My house ground is good, panels are good, no floating neutral. We went through the house and unplugged _everything_. Fridge, oven, dryer, microwave, my rechargable "Dancin' Cliff' bobblehead with kung-fu grip... You name it, it was unplugged.

Then, the electricians yanked the electrical meter outside, so that there was no juice at all flowing into my house from the pole.

The result? The Noise Of Doom is still there. If I hold a guitar (any guitar) up to the wiring, run into a battery powered amp, noise galore. So my wiring is still putting out some kind of EMI/RFI, even when it's completely disconnected from the pole with nothing plugged in that could be backfeeding into the electrical system inside the house.

It's comical at this point, but the good news is that the electrician was so stumped, he didn't even charge me. :D
 
MG-Chris said:
so that there was no juice at all flowing into my house from the pole.
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Weird.We just fixed a problem at work,we have had stray voltage (20ish volts) that you can feel when touching equipment.So we spent 5K grounding/bonding the f outta everything.That didn't help.Turns out the power company had lost a ground wire from a pole 100 yards away in a swamp and it was coming through the soil/concrete.It had been going on for 6+ years!

I have a recent noise issue at home with my AXEII/guitars so this thread is very interesting to me.Its new too,I used to be able to palm mute with a high gain patch and have it "bloom"(ala early Deftones)decay but now the noise overtakes it :-(
 
OT? I have one of these cables with a small switch in it. Seems it could be the source of some of my extremely bad noise off and on (bad contact in the switch when "on"?). Haven't tried another cable yet. Are these cables notorious for bad contacts? It figures in a way... KISS
 
Hey so what ever happend to this MG-Chris??? Did you solve the problem? This thread hasn't been updated for more than 2 years and I would like an update on this since I'm having similar problems at my home (but deffinetly NOT as bad as you!).
 
Interesting topic. I don't have major noise issues currently, but will likely be moving over the summer. I'm wondering if this is the type of issue that can be spotted during a home inspection if you ask the inspector to pay extra attention to the electrical issues. It would be nice to know about noise issues beforehand, though it would likely not impact a purchase decision as the only noise that bothers my wife is my guitar playing. ;)
 
It's strange that for so long no one made a coment on this... I found this thread doing a search of EMI noise in forums and this was one of the first ones to come up and after reading and realizing that the people commenting actually know what they are talking about I hope they came with a solution for this!
 
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