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Strange Hum

9/2/2005 3:36 AM
Greg	Strange Hum Hi Guys, I've just built a 5E3, using Ceriatone transformers and chassis and I have a very strange ground loop type problem. Whenever a guitar is plugged in to any of the inputs, the hum appears. It sounds like your standard ground loop and no, it's not the guitar being too close to a transformer. It is only there with a guitar plugged in and the jack socket mounted in the chassis. I tried a switchcraft non-shorting jack, using the chassis as ground, with no change. Interestingly, without anything plugged into that and the input not shorted to ground, the hum isn't there. Anybody have any ideas, as apart from using modern Marshall style plastic jacks, I can't get rid of it. Thanks Greg

9/2/2005 3:36 AM

Greg

Strange Hum

Hi Guys,
I've just built a 5E3, using Ceriatone transformers and chassis and I have a very strange ground loop type problem.

Whenever a guitar is plugged in to any of the inputs, the hum appears. It sounds like your standard ground loop and no, it's not the guitar being too close to a transformer.

It is only there with a guitar plugged in and the jack socket mounted in the chassis. I tried a switchcraft non-shorting jack, using the chassis as ground, with no change. Interestingly, without anything plugged into that and the input not shorted to ground, the hum isn't there.

Anybody have any ideas, as apart from using modern Marshall style plastic jacks, I can't get rid of it.

Thanks
Greg

Replies:

Al Lang Try another guitar. I'd put the sho... -- 9/2/2005 8:34 AM
Enzo With the non shorting jack, everyth... -- 9/6/2005 8:28 PM