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I get a funny hum sound when I coonect my guitar to my amp. If I touch the toggel swith or pots , it goes away. I figured ther must be some grounding problem. But just for kicks I disconnected the amp from the Extension cord and pluged the amp directly into the power socket in the wall and there is no hum. I cheked the extension cord sockets if ther was any leakage current with a tester and found none. Cld ther still be a problem with grounding with the guitar or wld it be the Extension cord?


Originally Posted by JocelynI get a funny hum sound when I coonect my guitar to my amp. If I touch the toggel swith or pots , it goes away. I figured ther must be some grounding problem. But just for kicks I disconnected the amp from the Extension cord and pluged the amp directly into the power socket in the wall and there is no hum. I cheked the extension cord sockets if ther was any leakage current with a tester and found none. Cld ther still be a problem with grounding with the guitar or wld it be the Extension cord?

quot;But just for kicks I disconnected the amp from the Extension cord and pluged the amp directly into the power socket in the wall and there is no hum.quot; That suggests that there is something wrong with the extension cord. I assume that both the amp cord and extension cord are 3-prong... I suspect that the round prong on the extension cord is broken or missing. You can test the cord with the ohm scale on a digital multimeter (a good tool to keep with your rig to check fuses and wall outlets).

If the extension cord does not have a good ground circuit, please do not use it... electrocution is no fun at all!


Originally Posted by BlueGuitarIf the extension cord does not have a good ground circuit, please do not use it... electrocution is no fun at all!
LOL Thanks for the reply. Yes u are right both the amp and the extension are three pronged. Three pronged is standard here for any high voltage device. like a house hold Iron, to my soldering Iron. I checked the sockets on the extension cord including the earthing but cld not find any lekage current. I guess the earthing might have gone short.

anybody else have any other opinons

Yeah, some electronic surge suppressor/extension module strips (like commonly used with computers, and home entertainment systems) are designed rather poorly and or cheaply (especially overseas knock-offs that are *supposed* to meet certain codes, but don't ...) occasionally an off brand won't have the ground connected properly, or won't be shielded well at all, and will pick up interference ... just because it has three prongs doesn't mean that all three are wired correctly (you might want to get a receptacle tester that plugs in the wall), you can check the wall, and then plug up the power strip or extension card and check that, if the ground is not wired correctly it will indicate it. Also, even if everything is correct, please note that running any AC power leads over other cables or across other electrical fields can induce noise and or hum into your amp via it's mains. So try relocating the extension cord/power strip and see if that makes any difference (I'd check to see that it *is* wired correctly first though).