Dedicated power

Ray, I said double-pole. You're correct, 30A breaker is wired to both legs; 240V.

https://www.homedepot.com/b/Electrical-Wiring-Devices-Light-Controls-Electrical-Outlets-Receptacles/...=

Yes, looks like a dryer receptacle

There's no need for a 30A circuit. Listen to @cleeds .

Two 20A breakers, 20A hospital grade or audiophile duplexes, and 10/2 or 12/2 Romex. The lines from the service panel should be run with 12" separation from each other.
It's important to wire the lines to the same (leg) phase in the panel. Any high-current-draw appliances such as refrigerator or air conditioner should be moved to the opposite leg.

With all the electrical threads containing valuable knowledge by experts such as jea48 and Almarg, why are there now so many recommendations for a 30A circuit to power an audio system?
Plus 30 amps requires a dual-pole breaker. That means the dedicated line is tapped into both both legs. 

https://www.homedepot.com/b/Electrical-Power-Distribution-Electrical-Panels-Protective-Devices-Circu...=

30A dual-pole breaker.

Thanks, @jea48