20 Amp Dedicated line: 10 gauge vs 12 gauge wire

From all that I've read, it's about voltage drop over the distance of the circuit run. At shorter distances from your breaker box (perhaps under 30') go with 12 gauge, at longer distances (50' or more) definitely use 10 gauge. I've seen some charts showing the voltage drop over distance, and it can be significant, but I can't find them now.
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Mr_Lewis, most of us running dedicated circuits have installed two or more. For example, in my minimalist two-channel system, I run three dedicated circuits: a separate 20 amp circuit for each of my Atma-Sphere MA-2 220w monoblocks, and a third circuit for the preamp and turntable. A fourth circuit is available for the occasional digital device.

The C-J Premier 12 amps would be happy to have their own circuit, as would the LP275M amps. Putting them all on the same circuit is, imo, a mistake.

It may also be beneficial to have the TV and digital equipment on a circuit separate from your preamps and from your power amps. Doing so may help reduce noise over the A/C lines feeding into other equipment.

Looks to me like you are a candidate for at least three dedicated circuits coming into your room. After installing the dedicated circuit(s), I encourage you to do some critical listening without the power conditioner. You may be surprised to find an improvement from taking it out of the chain, particularly with the amps.
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A good practice in installing the dedicated circuits is to keep all the runs of the same length to deal with the potential Almarg mentions.
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