directional cables?

???? I missed it before but that makes absolutely no sense. You can't separate the positive and negative alternations of a signal with a cable any more than you can have a magnet with one pole.

He's not talking about the positive and negative alterations of a signal. He's talking about the shield. Specifically, a shield covering a pair of conductors.

With such a cable, you can either connect the shield to one end or both ends. If it's connected to both ends, then the shield carries some of the signal current. If you connect it at one end, it's not, however it still provides shielding. It's sometimes referred to as a "telescoping shield."

Thanks for the responses.

What if my pre amp (or TT or phono pre) has no ground pin on the power cord, just the power amp? What orientation now for the shielded IC's?

What if my pre amp (or TT or phono pre) has no ground pin on the power cord, just the power amp?

Consider yourself lucky. Provided of course that the chassis meet Class II specs and don't actually require the safety ground. The safety ground is the biggest source of ground loop and other noise.

What orientation now for the shielded IC's?

Same as you would otherwise.

The safety ground isn't a ground in the traditional sense. It's just connected to neutral back and the service panel and serves as a path for fault currents should there be a failure in the AC mains in the equipment which might otherwise cause the chassis to go hot and create a shock hazard.

It doesn't serve any purpose with regard to component grounding.

Even if your piece of equipment is floating there is still return - most likely capacitive. Cell phone is getting this return thru your body (just a few pF). Radio signals are in fact induced in in the cable (since shield most likely does nothing to stop it) but because of skin effect they travel on the outside of the cable - shield (field inside cancels). As long as this shield is related to system ground shield will protect against electromagnetic and capacitive pick-up.