Amp buzzing

[kbc0124]

Hi,

Total beginner here. I've noticed when I turn on my new amp (a Laney RB3) I get a buzzing sound even without the bass plugged in and even with the volume on the amp turned all the way down.

I suspect that this is a "ground loop" problem and/or caused by insufficient grounding? The electric cord that comes with the amp terminates in a two-prong plug and says it need to be grounded.

However, I live in Dubai where we have the UK-type power outlets - there is no "prong" that comes out of the power outlet itself to fit into the plug to handle the grounding (I hope this makes sense). I am just using a plastic adapter on the two-prong plug to allow it to plug into the wall (which again is the three-hole type outlet like in the UK).

In any case, could this be the cause of the buzz? If not a grounding issue, any other ideas what it could be?

Thanks for your thoughts.

[craig.p]

The CORD says it needs to be grounded? Where does it say that? Sounds to me like someone put a 2-prong plug (or cord set) on the amp.

You don't have a ground-loop problem, because you'd need a ground connection to experience a ground-loop problem. You have a problem with insufficient SHIELDING.

I don't understand your description of the power outlets where you live, specifically regarding what's not present. Sort of scratching my head over that one.

Your owners manual ought to have instructions concerning suitable power for the unit.

[billfitzmaurice]

Originally Posted by kbc0124

Hi,

Total beginner here. I've noticed when I turn on my new amp (a Laney RB3) I get a buzzing sound even without the bass plugged in and even with the volume on the amp turned all the way down.

I suspect that this is a "ground loop" problem and/or caused by insufficient grounding? The electric cord that comes with the amp terminates in a two-prong plug and says it need to be grounded.

However, I live in Dubai where we have the UK-type power outlets - there is no "prong" that comes out of the power outlet itself to fit into the plug to handle the grounding (I hope this makes sense). I am just using a plastic adapter on the two-prong plug to allow it to plug into the wall (which again is the three-hole type outlet like in the UK).

In any case, could this be the cause of the buzz? If not a grounding issue, any other ideas what it could be?

Thanks for your thoughts.

It's not a ground loop, as that requires two pieces of gear, connected to each other and AC power. A lack of grounding is a possibility, as the amp cannot be grounded if it uses a two wire cord. I suspect by your description that you need a special cord or adaptor to connect the amp to your power that will ground. A visit to a local music store that knows about these things would be in order.

[kbc0124]

Thanks guys. Okay, I think it is a grounding issue. The cord coming out of the amplifier terminates with a plug like in the link here, with two prongs and a third "receptacle" for the grounding:

http://www.francetravelplanner.com/d.../electric.html

It is designed for a socket like in the link above, where the grounding prong is sticking out of the wall socket itself.

But in Dubai we have the UK-type power sockets, like this, where the grounding prong needs to be in the plug itself:

http://www.busytrade.com/products/16...er-Socket.html

So I suppose that the amp is not grounded with the plug adapter I am using. I think I need to either find a solution with some type of better adapter, or I need to replace the cord on the amp (it just plugs into the back of the amp so could be easily swapped if I could find a replacement).

Thanks for your help!

[kbc0124]

Quick update on this issue. I decided to just cut the plug off of the cord to the amp and replace with the correct type of grounded plug. After doing this, the buzz is still there. I guess I'll assume that this is normal? It's not a loud buzz - I had to be sitting in front of the amp to notice it. At least the amp is grounded now, which I think somehow makes it safer as an electrical appliance?