To Float or not to Float...

georgehifi

... This way there is no "earth loop" via the grounds and your house earthing. As all earths are carried to the all three components via the interconnects to the ones that aren't ...

This is extremely dangerous - interconnects are not intended to carry safety grounds. Following this practice means that a component's chassis could be energized with lethal voltage. Safety grounds should be "earthed" only through a properly grounded power cord, or a chassis that is itself directly connected to a safety ground.

georgehifi

If you were to have a grounded mains plug at the source and the poweramp you have created an earth loop with the ground wire between the power points as the interconnect carry the earth as well.

It is clear that you are confused about this issue. The matter of ground loops is only an issue when the grounds are of different potential. Having multiple safety grounds in an audio system is not itself an inherent problem.

As for interconnects carrying safety grounds again, you are confused, particularly with respect to balanced connections.

georgehifi

Look at most CD players, tuners, phono stages ect, they mostly have a figure 8 mains plug on the back yes just two pin, and yes it get’s it’s earth ref from the next stage ...

I thought we were talking about components manufactured in this millennium, which typically use IEC connectors and either have safety grounds or special construction to insulate the chassis. It’s rare for modern equipment to use figure-eight, two-prong AC connectors.

You might still be relying on obsolete knob-and-tube wiring in your house, too. But most of the world has moved on from that.

No matter how you to try to twist this discussion, @georgehifi , interconnects are not intended to carry a safety ground. And there is no inherent risk in having a system with multiple safety grounds. The goal is to have equal electrical potential of each ground - rather than to bypass safety grounds.

linndec

... if you have a ground loop "buzzing" noise lift the earth on the pre amp as interconnects can more than likely handle that current going back to earth.

This is bad advice and potentially unsafe. Interconnects aren’t designed to handle this current, and lifting the AC ground could energize component chassis with lethal voltages.

It amazes me how often people here misunderstand ground loop problems. The issue isn’t having multiple paths to ground; the problem is having multiple ground paths at varying potentials.

This is one of the benefits of using dedicated AC lines - it simply makes it easier to have clean grounds. I have a biamplified system with lord knows about many ground paths! I don’t have any hum issues, though, because of these clean, direct grounds ... all at the same voltage potential.