Ungrounding an Amp--Any Danger?

Yes, the story is that Keith Relf died from electrocution while playing his electric guitar at home. A common version has him playing it in the bathtub, but his family has said this is a myth and he was found dead in his basement recording studio. Supposedly his amp developed an electrical fault, and it's also said that he was probably standing on an exposed gasline pipe that had something to do with it. What's interesting about this to me (other than that I am a Yardbirds fan) is that I play electric guitar, and can vouch for the fact that the vast majority of vintage amps do not have 3-pronged plugs in the first place.

Nsgarch: High quality coaxial analog interconnects, if not prevalent, are indeed made, by van den Hul for instance (which I happen to own)...there are others...

Would somebody please explain to me what the Signal Ground Lift switch on the back of my amp is for? IN LAYMAN'S TERMS. I don't really understand electricity, you see. I believe the switch is currently lifted, but I've no clear idea what that did for me (again, in layman's terms). "Well, it needs to be either lifted or not," I thought to myself, and "lifted" seemed somehow the sonically appropriate term. Maybe I should have read the owners' manual..

My amp has a hum that you can only hear when your ear is right up to it; i.e. a pretty quiet amp? Is this the sort of (very subtle) hum people are complaining about? All my stuff is plugged into a power conditioner, which of course has three-prong receptacles, and the power conditioner is plugged into a (grounded) wall outlet. All of these important tasks -- so vital to turning the stereo ON, so you can, you know, LISTEN TO IT -- were accomplished on Day 1. I'd have thought that was the last thought I'd need to give to the matter of electricity, but maybe I'm just hopelessly naive.

Zaikesman, re the van den Hul "screened" (shielded) coaxial products: There are only two unbalanced cables which are spec'd. for audio signal transfer, and both of them use vdH's proprietary non-metallic "Linear Structured Carbon" as the shield. Since it's carbon (non metallic) it's not affected by EMI (hum) and does a pretty good job soaking up RFI.

But as I said in my earlier post (I should have listed it I suppose) this product is definitely a hybrid. Most of vdH's audio cables do use balanced (shotgun) conductors in fact. You can see them all at:

http://www.vandenhul.com/cable/c-cab-ty.htm#12

07-13-06: Skippack
My amp has a hum that you can only hear when your ear is right up to it; i.e. a pretty quiet amp? Is this the sort of (very subtle) hum people are complaining about?

No. What you describe is normal. A ground loop hum can be heard from several feet away, or more.