Separate ground for dedicated line

If you run 2 grounds it would be: a) illegal in most places, and b) a sure-fire recipe for ground loop hums.

A ground is by definition at one point and that point is at the service entry. You are really not gaining anything and giving up a lot safety-wise with two or more separate ground points.

If your service is buried then your ground is most likely a ground rod. But it could be the water pipe also. Just bring the grounds back to the main panel the way it's supposed to be. Isolating the grounds from the receptacle boxes (if using armored cable) is all you need to do to minimize common mode noise from EMI/RFI.

Re the shield on the belden 83800 series. If you're using the simpler 83802 12/2, then of course connect the twisted shield at both the breaker bus and your outlets' grounds.
If using 83803 12/3 then you can ignore the inner shield OR connect it at the breaker to act as a drain. RSVP for more info. Cheers.

I spoke to an electrical engineer who said that both dedicated lines as well as dedicated grounds can cause ground loop noise even if everything is grounded to one common utility ground poll. He recommended having as many stereo units on one line as possible. Is there any logic to this?

Yes, except that you ALWAYS want to isolate the RF-noisy digital components from the low-level analogue (CDP, phono pre, tuner, etc.). So if you run only ONE dedicated line keep your CDP OFF it! Better to run two lines...one for digital and one for analog. Even better to run THREE if you have big monos, so they can have their own fatter one. RSVP for more info....Ern

Subaruguru, thanks for your help. I have two Mark Levinson 334 dual mono blocks, and one Bryston 7BST single mono block for the sub. I'm afraid that all of these amps can draw mucho amps when taxed. I have one 20 amp circuit for the Bryston and three 15 amp circuits for the two Mark Levinsons and the CDP. Do I need all four circuits or is this overkill?