Hello all,

I wonder if I could get some opinions.
I have a small (around 5w) guitar amp which is from the 60s.
Its an american made (2pin plug) amp and I have a step converter to allow to run in UK.

The problem is that, as the thread title suggests, it keeps electrocuting me. Not only have i had shocks from the cable plugged into the amp, I've also been shocked by touching other metal components of equipment that has been connected to the amp.

Its a rare and excellent sounding amp, and I don't want to lose it. I've had it serviced and it still is giving me shocks. I asked the tech who serviced it what was going on and I just got incoherent ramblings about america, the 60's and it not having an earth. (i get the last bit)

so what are my options here? Is getting it earthed even a possibility? Is it something specific to an american amp being run in the UK, or is it simply broken somehow?

I'm also wondering in the step down converter is playing a part, as it makes a loud buzzing noise, even when the amp isn't plugged into it.

thanks in advance for any advice

Tom
 
Sounds like it needs earthing correctly but the step down isn’t doing this. Ideally you need the amp testing by a specialist to confirm.
 
If you are getting shocks from the amp (and connected equipment) there is probably a wiring fault or insulation breakdown in the amp itself. Just because it isn't earthed, doesn't mean it should give you shocks. Many devices were not built to today's safety standards, especially those made for 120V, but they were expected to be generally safe to use.

The stepdown transformer is probably of the normal 'autotransformer' type that does not provide isolation between the 230V input and the 120V output. If so, there is a possibility that a wiring error on the transformer can make things more dangerous by referencing the 120V output to the 230V line of the input rather than the neutral. This will not cause shocks itself but will make any defect in the amp and resulting shock possibly more dangerous.

I would get a specialist to look at the amp. I used to service a lot of music gear and it was rare that things couldn't be made safe and shockproof, and it didn't always require adding an earth. If the cause of the shocks is located and there is no easy fix for it, then the existing 230-120V stepdown transformer can be replaced with an isolating transformer. This will almost certainly eliminate the shocks, but will conceal the existing fault that is causing them. So you should have the amp carefully checked first, before resorting to using an isolating step-down transformer.
 
Thanks Lucien,

that's a really useful summary.

Do you know if there is a specific kind of electrician who might specialise in vintage gear, to help my search?

(also i notice many people are amused by my misuse of the word electrocution... which makes me wonder, when does a shock become an electrocution??)

thanks again

Tom

If you are getting shocks from the amp (and connected equipment) there is probably a wiring fault or insulation breakdown in the amp itself. Just because it isn't earthed, doesn't mean it should give you shocks. Many devices were not built to today's safety standards, especially those made for 120V, but they were expected to be generally safe to use.

The stepdown transformer is probably of the normal 'autotransformer' type that does not provide isolation between the 230V input and the 120V output. If so, there is a possibility that a wiring error on the transformer can make things more dangerous by referencing the 120V output to the 230V line of the input rather than the neutral. This will not cause shocks itself but will make any defect in the amp and resulting shock possibly more dangerous.

I would get a specialist to look at the amp. I used to service a lot of music gear and it was rare that things couldn't be made safe and shockproof, and it didn't always require adding an earth. If the cause of the shocks is located and there is no easy fix for it, then the existing 230-120V stepdown transformer can be replaced with an isolating transformer. This will almost certainly eliminate the shocks, but will conceal the existing fault that is causing them. So you should have the amp carefully checked first, before resorting to using an isolating step-down transformer.
If you are getting shocks from the amp (and connected equipment) there is probably a wiring fault or insulation breakdown in the amp itself. Just because it isn't earthed, doesn't mean it should give you shocks. Many devices were not built to today's safety standards, especially those made for 120V, but they were expected to be generally safe to use.

The stepdown transformer is probably of the normal 'autotransformer' type that does not provide isolation between the 230V input and the 120V output. If so, there is a possibility that a wiring error on the transformer can make things more dangerous by referencing the 120V output to the 230V line of the input rather than the neutral. This will not cause shocks itself but will make any defect in the amp and resulting shock possibly more dangerous.

I would get a specialist to look at the amp. I used to service a lot of music gear and it was rare that things couldn't be made safe and shockproof, and it didn't always require adding an earth. If the cause of the shocks is located and there is no easy fix for it, then the existing 230-120V stepdown transformer can be replaced with an isolating transformer. This will almost certainly eliminate the shocks, but will conceal the existing fault that is causing them. So you should have the amp carefully checked first, before resorting to using an isolating step-down transformer.
 
I'm more like the bee-gees... just interested in stayin' alive


Hello all,

I wonder if I could get some opinions.
I have a small (around 5w) guitar amp which is from the 60s.
Its an american made (2pin plug) amp and I have a step converter to allow to run in UK.

The problem is that, as the thread title suggests, it keeps electrocuting me. Not only have i had shocks from the cable plugged into the amp, I've also been shocked by touching other metal components of equipment that has been connected to the amp.

Its a rare and excellent sounding amp, and I don't want to lose it. I've had it serviced and it still is giving me shocks. I asked the tech who serviced it what was going on and I just got incoherent ramblings about america, the 60's and it not having an earth. (i get the last bit)

so what are my options here? Is getting it earthed even a possibility? Is it something specific to an american amp being run in the UK, or is it simply broken somehow?

I'm also wondering in the step down converter is playing a part, as it makes a loud buzzing noise, even when the amp isn't plugged into it.

thanks in advance for any advice

Tom
...Don't know what's wrong with the bands of today...an electrocuting amp,would at one time,just be Keith Moon's latest practical joke...;)
 
Thanks Lucien,

that's a really useful summary.

Do you know if there is a specific kind of electrician who might specialise in vintage gear, to help my search?

(also i notice many people are amused by my misuse of the word electrocution... which makes me wonder, when does a shock become an electrocution??)

thanks again

Tom
you survive a shock. electrocution is fatal.
 
Technically your not getting electrocuted as that means you would be dead. Your probably getting an electric shock though.

electrocution is fatal

Oxford Dictionary: electrocute = Injure or kill (someone) by electric shock

So not always fatal.
.......IN YOUR FACE.....
(If I could dance round the office while shouting the above I would...)
 

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