I remember a dude plugged in and touching his guitar barefoot on wet ground.
 
'I feel funny,' He said.
 
Shoes, dude. Shoes.

 

firebird
I've seen problems where two amps are plugged into the same AC power strip (same outlet) and there is a ground loop hum problem.

Unless those 2 amps you are talking about are running in to each other (connected together), it isn't going to mean anything.
You can have all the ground problems  in the world, but if you want to narrow down your problems, go through one outlet.

What I was referring to and didn't make clear with two amps is when someone is connecting their guitar, for example, into two amps.  Even plugged into the same power strip there can be a ground loop hum (and often is).

fireberd
What I was referring to and didn't make clear with two amps is when someone is connecting their guitar, for example, into two amps.  Even plugged into the same power strip there can be a ground loop hum (and often is).

If the amps and guitars are properly grounded you won't.  
 
This also applies to the other scenarios you pointed out, I believe.  Sounds like a grounding issue with the gear, not a ground loop problem itself.  

This is a GREAT thread.  There's some tremendously good advice here.

jude77
This is a GREAT thread.  There's some tremendously good advice here.

Some good debates too
but your right, good readings. everybody's opinion seems to make this forum a great place.

chuckebaby

jude77
This is a GREAT thread.  There's some tremendously good advice here.

Some good debates too
but your right, good readings. everybody's opinion seems to make this forum a great place.

Exactly!!  it's one of the things I love about this place.

Brian Walton

fireberd
What I was referring to and didn't make clear with two amps is when someone is connecting their guitar, for example, into two amps.  Even plugged into the same power strip there can be a ground loop hum (and often is).

If the amps and guitars are properly grounded you won't.  

It can happen, depending on the amps being used. Often a simple one into two lead or passive switchbox or a buffered splitter or the outputs from a stereo pedal does the job with no problems, but sometimes it doesn't.

And if it doesn't Lehle make very nice transformer-isolated splitters to deal with the problem.

There might be a phasing issue as well of course, depending on the amps and how the speakers are wired.