3

Today I noticed that if I touch both the guitar strings (while connected to the amplifier) and the metallic radiator in my room, I can feel a current flowing (nothing too strong).

Does this mean the amp might not be properly grounded?

It's a 15 watt Marshal 3 wire plug amp.

4
  • 2
    The question may be more appropriate for Electrical Engineering, but do you measure a voltage between metal parts of guitar and radiator? I find sometimes the sensation comes from the metal just being cold.
    – user43681
    Nov 5, 2017 at 22:10
  • 1
    It certainly means that you shouldn't use that setup again until it's been checked by someone who DOES understand such things.
    – Laurence
    Nov 5, 2017 at 22:38
  • @YeDawg I'm borrowing a voltmeter tomorrow to see how much it is exactly. At first I thought the radiator was shaking or something, but no, I checked multiple times, (touching the radiator without touching anything, etc) and it definitively is a current passing through
    – Chapi
    Nov 6, 2017 at 0:27
  • It is also entirely possible that your 3 plug wall outlet isn't properly grounded.
    – Paul
    Nov 6, 2017 at 15:48

1 Answer 1

2

If you can use a multimeter, don't bother plugging the amp in. It sounds like there is a problem. To check earth continuity, switch the meter to continuity and touch one probe to the earth pin, other to chassis - or your guitar strings. No buzz or quiet buzz means a bad earth. You could also use the resistance part of the meter if you know what you're doing.

But it would be best to take it to a repairer before using it again.

It would also be worth checking the socket used, partially by plugging into another socket, preferably in a different room or level from the one normally used.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.