Re: eliminating ground hum by eliminating ground pin

Apparantly it is dangerous to use an adaptor which gets rid of the ground pin on an electric cable, as if there is a power surge, you can get electrocuted. However is it still dangerous if the device is plugged into a strip which has a surge protector?

Chony

Yes, it's just as dangerous. Earth grounding of equipment mostly isn't intended to protect against surges, and surge protectors don't eliminate shock hazards. Sometimes, due to a failure of insulation or other cause, powerline ("mains", for folks in Europe)AC voltage can wind up connected to the chassis/housing of an electrical device. The ground connection is intended to divert that possibly lethal voltage to ground, and not through YOU, or other connected equipment. A side benefit is that if enough current goes to ground, it will trip the equipment's protective fuse or circuit breaker.

In some cases, a GFCI (Ground Fault Circuit Interrupter) type outlet can protect you and your equipment in the event of a failed (or perhaps intentionally removed) protective ground. However, I DO NOT recommend ever removing a powerline ground just because a GFCI outlet is available; GFCIs have been known to fail!

Usually people using audio equipment remove the ground pin, or improperly use an adapter to "lift" it, because they are experiencing hum or other types of noise problems caused by a ground loop. It's almost always possible to find and eliminate the problem without resorting to disconnecting the ground, and I'd urge anyone thinking of doing that to think again.

Chony, if you are having a hum problem, please describe the circumstances in detail, and I'll try to help you resolve it safely.

--Barry

Hi Chony,

As quietDIN pointed out, lifting the ground by using an adapter or by removing the ground pin is NOT the way to solve a ground hum problem (if that is why you are asking "?")

There is always a reason why hum exists and it is best to find the source and then solve the problem correctly (and safely).

One thing I always keep in my gig bag is a Hum Eliminator by EBTECH. Click HERE to see this device. The Hum Eliminator has helped me out on many occasions. You simply insert it between the keyboard or other audio device and the mixer/amp and it removes the offending hum.
The small unit has two inputs and outputs and requires no eternal power. There is a larger rack mount version with more ins/outs if necessary.

The link I supplied also has some good information on just what ground loops are and what causes them.

I hope this is useful to you.

Best Regards,

Dave


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Wm. David McMahan
Nat'l Product and Support Manager
Generalmusic USA
GEM Community Forums

Thank you both for your replies.

I'm not currently experiencing ground looping problems because I recently divided my equipment between my recording room and mixing room. Since I've done that, the conflicts seem to have been eliminated.

But I was thinking about ground loop, and came up with this "brain storm" so I thought I'd ask those wiser than myself!

Thanks again, Chony.

You're welcome, Chony. I'm glad to offer advice that might prevent someone or their equipment from meeting an early demise. It's good that you were able to resolve the problem you were having without removing the powerline ground connection.

--Barry

This is a good explanation of noise problems. http://www.taylorguitars.com/video/noise-reduction.aspx?play=hi

Hank