Dedicated 20 amp circuit. 10/2 or 10/3?

Another reason to have a circuit from each side would be if you found one side noisier than the other you could plug everything into the less noisy side.

Remember the threads of people trying to find mysterious noises?  switching to the other leg will usually solve that problem.

If the device count is modest and the power low, 10/2. If you want multiple outlets and really want 2 dedicated circuits, 10/3.

Also, consider running 10/2 at 220V to a step down, balanced transformer in the room. If this is a long run this can be especially beneficial.

10-4 that is what I had installed.

my friend is a master electrician and Audiophile 

you have live ,neutral and 2 grounds a common ground ,and a insulated isolated ground in its own conduit , then has its own smaller buzz bar the 20 amp 

breakers are industrial silver over Copper which means like regular breakers that are copper should be replaced every 4-5 years because of oxydation,

and use gold plated Copper outlets ,  breakers were made by Siemens Germany 

I tried getting them for my friend very hard to obtain since covid.

underwood Wally has a plug in device Puron ,buy the better ones with the Furutech 

gold copper $350:, the cheaper ones $250 and 3x less conductive Brass, check them out they truly clean your line further ,even if you have a very good line conditioner.

I have a 20 amp dedicated line and I believe it’s its a 12/3 cable on two duplex boxes.  One has the power conditioner on it and the other has the amps plugged into it.

 I haven’t changed outlets mostly because if I ask five people about it, I get five different answers.

One can run 10/3 romex for 220 single phase to a location, and run with it a 12g. green ground with it.  Perhaps not 'according to Hoyle' but at the business end one can 'split' into 2 - 110 circuits and still have the 'safety' mechanical ground....

Label what you've did/done....at each end.....

It's not nice to 'leave mousetraps' like that, and keep your amp loads balanced.

Cooking one side generally takes the other with it...just to make the point....;)