Troubleshooting Guitar Amp Electrical Issues in Apartment

  • Thread starter MasterBlaster
  • Start date
  • Tags
    Electrical
In summary, when the user plugs their guitar amp into any outlet in their apartment, a local radio station comes through the speakers at a low volume. This also occurs when using headphones, leading the user to believe it is not an issue with the amp itself. The user is seeking advice on what electrical mistakes or issues could be causing this and if there are any common solutions. In response, it is suggested to ensure the signal ground is isolated from the power ground to prevent the chassis from acting as an antenna. The use of a 3-prong outlet and a shielded cable is also recommended. The user then explains that they are experiencing buzzing in their amp speakers and computer speakers, and that bypassing the computer eliminates the issue. It is
  • #1
MasterBlaster
When I plug my guitar amp into any outlet in my apt. I get a local radio station coming through the speakers in low volume. If I bypass the speakers and use headphones it still comes in so it will come out of any of the outputs.

Although I have not tested this amp at another place in a long time, I do not believe it to be the amp.

What electrical mistakes/issues could be causing this?
 
Computer science news on Phys.org
  • #2
Furthermore - are there any common pieces I can add to the electrical cable plug into stop this? It's something coming through the electrical cable...
 
  • #3
Make sure the signal ground is isolated from the power ground... otherwise the chasis will act as one big antenna.

eNtRopY
 
  • #4
Originally posted by eNtRopY
Make sure the signal ground is isolated from the power ground... otherwise the chasis will act as one big antenna.

eNtRopY

Can you explain this in layman's terms?

Thanks!
 
  • #5
You should be using a 3-prong (grounded) outlet, do not use an adapter on your power plug that eliminates the round ground pin.

Also, you could try using a different length cable between your guitar and the amplifier input. If you can find a shielded cable for this, that would be better.
 
  • #6
Originally posted by MasterBlaster
Can you explain this in layman's terms?

Thanks!

There are usually two grounds in an electronic system. One is for power and one is for signal. The power ground is always noisy, and usually the case of the system is grounded to it. The signal ground is a clean ground. It is used as a voltage reference for the music signal. You don't want this ground to be connected to the power ground. It will cause your signal to be noisy, and it is possible that the case will act as an antenna imposing radio signal on your guitar signal.

eNtRopY
 
  • #7
So entropy - My issue know lies in the fact that when I have my amp plugged through my system to my PC, I get a buzzing in the amp speakers as well as in the PC speakers.

And when I bypass my computer and just run it to the PC speakers, I don't get the buzz.

This led be to believe that somehow the cheap mobo soundcard or the computer itself is causing this buzzing, however the buzzing also requires my amp to be plugged into the wall. Weather or not the amp is on or not doesn't matter, just that it is plugged in.

SO it's like it requires both those things to buzz.

So I went and got a cheap soundcard to try it. Not only does the buzzing still occur, but when I strum my guitar the monitor get slines on it, and a hard strum causes the monitor to black out and the green light goes yellow for a second.

So what the hell. Either my computer (not the mobo soundcard) is doing it - or the amp is sending some bad power signals into the lines and distorting the damn computer ****.

My only guess is to take the amp into the store. The guy said it didn't sound like my amp was the issue - but i dunno.

Any ideas? I know it's complicated but I am **** out of luck for answers!
 
  • #8
Whenever you hear buzzing coming through the speaker, it means you have a ground loop. That is to say that you are grounding your signal electronics with two different grounds in two different places. Since the two grounds have slightly different voltage potentials, there is a DC current passing through your electronics. This current is generating thermal noise.

What you need to do is protect your computer from your amp by using an isolation transformer.

eNtRopY
 
  • #9
Ok Entropy - thanks alot... a bit more questions for your smart brain.

First off catch my other post about this - since I've isolated the issue to much fewer pieces of equipment it may help. Let me know what you think in there as well if you please.

You mentioned the isolation transformer - since in my other post I show that this issue doesn't need to involve the amp at all, let me know what you think about that.

Also - the type of cord i use to run the amp to the PC is a large size jack, the 1/2 inch i guess it is.

Do isolation transfomers fit that? And would they have those at radio shack? thanks!
 
  • #10
Question: Is your computer properly grounded? Are you using the third grouding prong on the outlet plug? Are you certain that ground of your wall outlet isn't floating?

All the things you have described so far, in this post and the other, are indications that you have a ground loop in your system. Since, you say that have problems even when you don't plug anything into your computer, I have to wonder if the ground of your computer is floating... that is to say, I have to wonder if your computer is not grounded at all.

eNtRopY
 
  • #11
Ok entropy - I am indeed using the third prong of my computer.

Originally I had my PC in one of those power strips to a power plug. Instead I tried putting the power plug into the same outlet that the strip was in.

So this floating issue - is that an issue at each outlet?

Would it be a good idea to try a different outlet? Or would the floating issue be something that would not change at a different outlet.../
 
  • #12
Sure, try another outlet. Maybe the wall outlet is floating. If that doesn't work... take two of these and call me in the morning.

eNtRopY
 
  • #13
I will try another one and get back to you.
 
  • #14
I tried another outlet. Identically the same.

DX posted in the other column trying unplugging each device to see if one is malfunctioning. Since this is easy to do I will go do it now.

But I plan on speaking with the front desk tommorrow - I will tell them "an electrician at radio shack told me it could damage my computer". So it will give them a reason to fix it. At least send an electrician to assess the problem!

Anyhow - with all the ****ing testing I have done I am just going to suck it up if they won't fix it. It has to be inside the walls...

thanks fer all the help entropy
 
  • #15
Originally posted by eNtRopY
Are you certain that ground of your wall outlet isn't floating?

All the things you have described so far, in this post and the other, are indications that you have a ground loop in your system. Since, you say that have problems even when you don't plug anything into your computer, I have to wonder if the ground of your computer is floating... that is to say, I have to wonder if your computer is not grounded at all.

This sounds like a prime candidate for the problem.

Crystal, I'm guessing you could probably get a ground tester at radioshack. If it indicates a bad ground, you may need to rewire your house or at least the outlets you wish to use for this purpose.
***use extreme caution if you try this yourself***
 
  • #16
buzzing guitar and computer

Guitars can pick-up the AC humm from a standard PC monitor and put it thru the signal line. Turn volume all the way down on your guitar or turn off your monitor(s) from the front panel, does this change anything? If you have an LCD monitor forget about what I said. Also, are there any touch lites or flourescent lights in the room, maybe on the same breaker? Does the room you play in have a concrete floor? Bare or under carpet? Are you using any effects? Tuners, pedals etc... if so, and they use wall-wart power adapters, try using a 9 volt battery instead of A/C.
 
Last edited:
  • #17
The do sell isolation transformers for most audio connectors. Radio Shack might not have them, but a good music store probably will.

All of the items mentioned so far could be causing your issue.
However, the cure might be as simple as flipping the isolation polarity switch on your amp.
If it has one.

Also, you might not need to use the amp if all you are trying to do is get sound in your PC.
Try an adaptor connector and plug guitar directly into sound card.
 

1. How do I troubleshoot a guitar amp in my apartment?

To troubleshoot a guitar amp in your apartment, first check the power source to make sure it is plugged in and turned on. Next, check the cables and connections to ensure they are secure. If the amp still isn't working, try swapping out different components, such as the guitar or pedals, to determine if the issue is with the amp itself.

2. Why is my guitar amp making strange noises?

There are a few possible reasons for strange noises coming from a guitar amp in an apartment. It could be due to a faulty cable or connection, interference from other electronic devices, or a problem with the amp's internal components. Try eliminating these potential causes one by one to determine the source of the issue.

3. How can I prevent my guitar amp from blowing fuses in my apartment?

To prevent your guitar amp from blowing fuses, make sure you are using the correct type and rating of fuse for your amp. Also, avoid overloading the amp by using too many pedals or connecting it to other high-powered devices. If the problem persists, it may be a sign of a larger electrical issue that requires professional help.

4. What should I do if my guitar amp won't turn on in my apartment?

If your guitar amp won't turn on, first check the power source and make sure it is connected and functioning properly. If the power source is not the issue, try resetting the amp by unplugging it and plugging it back in. If it still won't turn on, there may be a problem with the internal components that requires further troubleshooting or professional repair.

5. Is it safe to use a guitar amp in an apartment with limited electrical outlets?

It can be safe to use a guitar amp in an apartment with limited electrical outlets as long as you are mindful of how much power the amp is using and do not overload the circuit. Make sure to not plug in too many other devices in the same outlet or circuit as the amp, as this can cause electrical issues. If you are unsure, it is always best to consult a professional electrician for advice.

Similar threads

Replies
6
Views
2K
Replies
21
Views
1K
  • Art, Music, History, and Linguistics
Replies
13
Views
3K
  • Electrical Engineering
Replies
7
Views
1K
Replies
4
Views
8K
  • Electrical Engineering
Replies
6
Views
1K
  • Electrical Engineering
Replies
1
Views
915
  • Electrical Engineering
Replies
19
Views
1K
  • Electrical Engineering
Replies
4
Views
1K
Replies
12
Views
1K
Back
Top