What type of wire for dedicated 20A AC lines?

1st, have a look at the guage of a fuse in any of your equipment. Now let’s just give that tiny wire some clean juice.

Get thee a power conditioner, all the power comes from it’s internal capacitors.

here's a customer return, darn good price

plug nearly everything into it, one switch power on/off

I got some very good advice about dedicated lines, including from members here and from Chris Venhaus at VH audio. Here's a compilation of some of that advice.

If there are multiple dedicated outlets...

Wires between the breaker panel and the dedicated outlets:
same type
same size
same length
be continuous (ie, no splices). 
Identical wire lengths ensure that each outlet's ground path is identical and that no ground loops are created. 

Wire must be:
copper, not aluminum
be 10 AWG or thicker

If you run a Subpanel it should be:
powered by a single phase from the main panel
wiring between the main panel and the subpanel should be 8 or 6AWG

Breakers in subpanel feeding audio lines:
should be silver-tungsten (not copper) contacts
Use silver paste on the breakers' screw terminals
Use silver paste on the contacts in the AC outlets that attach to the wire
McMaster #1219K57 silver paste is ideal

All contacts between breakers and wire should be clean, tight, and treated with silver paste

Good discussion, thank you.  Just to reiterate my question:  what “10 AWG or better” wire to get, that is solid core copper.

So, assuming I wanted to get this caliber of wire, which should I get and where do I buy it?

Any electrical supply house will have 10 AWG solid core. Home Depot, too, I'm sure.

@nyev

I assume you live in the US...

Solid core #8awg 600V insulated power wiring hasn’t been made in years. Insulated #10awg is the largest solid core wire made...

For a 50ft run, length, #10 should be more than adequate. I doubt if pushing the amp hard playing music with high dynamics will cause any VD, (Voltage Drop), on the branch circuit wiring.

Here is a review quote from Six Moons on the amp:

Gryphon are purists. For electronics that’s fully balanced, dual mono, DC coupled, high bandwidth and zero NFB. With 200W idle and 1’900W max power draw

I am not sure if the 1900W is continuous or short, quick, draws of current that would be caused from pushing the amp hard playing music with high dynamic passages. 50ft of #10awg should handle the load without any AC Line VD. Power amp’s power supplies like a steady state AC mains voltage.

As for the type of branch circuit wiring to use I would recommend 10-2 solid core with ground MC, (Metal Clad), aluminum armor cable. * MC, NOT, AC armor cable *... 2nd choice 10-2 with ground NM-B, (Romex Trade Name), sheathed cable.

Breaker size 20 amp

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