15A vs. 20A power cord questions

asp307 said:
"I’m installing dedicated 20A lines with 10AWG cable"

Lines? More than one.

Not knowing what the wiring layout method will be for the NM-B cable installation, if possible after the electrician gets out of the electrical panel and starts the horizontal parallel runs of the cables ask him if possible to keep them separated from one another by at least 12". If they are installed right next to one another for several feet when a connected load is connected to the cables the current carrying hot and neutral conductors magnetic fields will induced AC voltage/noise onto one another. (Same reason why dedicated branch circuits should never be installed in a conduit or raceway with other branch circuit wiring.)

Have him keep the dedicated branch circuit NM-B cables away from any other branch circuits that may have light dimmers connected to them. The load side wiring as well as the line side feeding the dimmer, (when turned on light/s dimmed), emits Harmonics RFI as far as 3’ to 5’ in all directions from the wiring. (The wiring becomes an antenna). If your new dedicated circuits are closer than 3’ the wires will pick up the RFI from the dimmer emitting wiring.
https://www.youtube.com/watch?v=OCK5W9vlAE0

When he connects the branch circuits to the branch circuit breakers in the electrical panel make sure they are all fed from the same Line,leg. All from Line 1 or all from Line 2. Not from both.

Have him verify they are all connected to the same by using his volt meter and measure for voltage from the Hot contact of one duplex receptacle dedicated branch circuit to the Hot contact of all other dedicated circuits duplex receptacles.

If they are all fed from the same Line, leg, he will measure zero volts. If he measures 240Vac nominal between any of then they are fed from both Lines.

For audio equipment connected together by wire ICs you want all the equipment fed from the same Line, leg.

I installed two dedicated circuits using #10-2 with ground MN-B cable.

One for digital and the other for analog.

It’s you call if you want to spend the extra money for the other line.

Because you are using #10 branch circuit wiring you should not have any fluctuating VD, voltage drop, problems playing moderate to loud dynamic music through your amp. And because all your equipment is analog one dedicated circuit is probably all you will ever need.

If you think there is a chance some time down the road you may add some digital equipment to the mix you could have the electrician install another cable now for future to a separate cut in wall box. Just have him put a blank cover plate on it for now. At the electrical panel he could terminate the neutral and equipment ground wires and tape off the end of the black hot wire for the future if you decided to use it. Extra price? Material plus just a little more labor cost. Definitely cheaper now than later. Future hook up cost? One hour labor rate, should cover it.

Who says an old dog can't learn new tricks.

Thank you for enlightening me. No isolated ground rod.