10/3 or 10/2 to each outlet?

I would run 10/2 w/ ground or run an isolated ground which is essentially an extra ground that runs along with the 10/2 w ground. 30-35 feet is nothing. You are already home running 10/2 to each duplex outlet. That's plenty of separation. Just make sure your ground is good. All this can be for naught if your house ground is inadequate. You might look into a ground rod just for the 4 runs to the system. This is where isolated ground hook up could be beneficial. Then the extra ground could go to the rod and really be effective if the rod is installed correctly.

Canucks0:
Using a sub-panel to shorten the lengths of the runs is a good idea. Be sure to use adequately sized feeders to the sub-panel. It is also true that for 10 Ga, a 35 foot run is not a big deal. However, if you use a well placed sub-panel, you will minimize costs for cabling.

Theo is right about the 30A breaker. This is, IMO, a very bad idea. Theo's suggestion about 14/4 is interesting and worthy of consideration. You might also do a review on his website the ideas that Russ Andrews recommends.

Chriskeating brings up the point of verifying your ground system. This cannot be overstated. This should be done first. See the thread http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1102789057
for a thorough discussion of grounding systems and AC issues. Seperating the ground source for the runs to the audio equipment (seperate from the house system) is a no-no according to many local codes. Yours may vary. Some seem to have done it with success. If you add ground rods and bond them together you still get much of the benefit.

Using 10/3 in the manner you described with individual hots and a shared neutral and a shared ground is also a bad idea. Sharing the ground....maybe. I would not do it, but then I may be particular. Sharing the neutral is a very bad idea as you are then placing twice the return current flow on ONE conductor AND sharing all of the noise.

The thread above talks about a lot of this in great detail.

Thanks guys. So the only reason for using 10/3 with dedicated lines would be to use the extra hot as an isolated ground. Do you use an isolated ground only in the instance where you have a sub panel needing its own grounding rod? Ideally I'd like to use the main panel's grounding system and breakers from there. How do you wire each outlet in a duplex separately so that each are dedicated. Do I need 2 runs of 10/2 to each duplex? Can I actually use 10/3 for this application? Thanks again. I am just concerned that if I am going dedicated, a CD player and processor sharing the duplex is not really dedicated. How can I separate? My plan once this is sorted out is to run an outlet box with all these duplexes(4) within it. Might do 2 separate boxes with 2 dedicated duplexes in each mounted to the floor.

Jeffcot is abslutely spot on about sizing the run to the sub panel correctly. Any potential benefit from shortening the individual runs can be lost by undersizing the feed to the panel. If you use this method, be diligent about checking polarity when you hook up your system for the first time. Don't assume that the electricial has wired everything properly.

Dave, first of all your electrician will run the wiring according to code - regardless of what you suggest to him. The only thing he'll consider is wire that is sized bigger than required that will physically fit the outlet or breaker. For example, he won't accomodate you with a 30-amp branch circuit breaker, floor outlets, 10/3 wire with common neutral or a secondary ground. All are no-no's with respect to NEC and most local codes - he'll explain why.

If you want an isolated ground, ask for "hospital grade" wiring, aka "Type MC" cable. This aluminum-armored cable comes with the extra green wire, that is 10/2 MC will have a black white AND green whereas 10/2 "regular" (or BX) will only have black and white. Regular BX 10/3 will have black, white and red - no green. Can't use RED for ground with most codes. If you're using Romex, then the green comes with the wire - that is, 10/2 romex has black, white and green.

The use of 10/3 wire is intended to be used in switched outlets where you want to continue the circuit power independent of the switch to the next outlet. Commonly used at receptacles that are switched on by a light switch and ceiling fans with separate motor and light control. Sometimes it's used by stingy homeowners to run two circuits with one neutral - saves a run of cable.

Installing a sub-panel is a very good idea if you can swing the cost. Your electrician will be able to recommend the correct size for your application. I would overkill the wiring to the subpanel by sizing them according the the panel rating. E.g., if it's a 100-amp subpanel run three #3 wires in 3/4-inch EMT, if it's a 60-amp subpanel, run three #6 in 1/2-inch EMT. Again, trust a competent electrician above all else.