Not trying to start any argument here, but there is absolutely no reason for the equipment to be on the same phase at all. The AC is converted to DC within the device, so AC voltage phasing is irrelevant.
As long as the dedicated line have hot, neutral and ground going back to the panel and do not share neutral or ground before the panel. you are fine.
Also, any electrician worth their salt will want to have your AC panel loads balanced on both phases.
I read that many posts about dedicated lines and some advocate placing them on the same phase. But, if your equipment carries a large load =, that load must be balanced on the AC panel to avoid overloads.
I ran dedicated lines for my audio equipment. My house fortunately is on a raised foundation, so crawling underneath the house was the way to go. Hot, neutral and ground all back to the panel and not shared.
I have to Audio Research REF 250 mono amps connected to the individual dedicated lines back to the panel (on the same phase at the panel) and one Mark Levinson 23.5 connected to the other phase via a dedicated line.
My low level equipment are all connected to a Transparent Audio Power Isolator 8 line conditioner, then via a dedicated line back to the panel.
I tried to balance the loads as best I could.
Noise floor is just gone. No ground loops, no buzz, no noise whatsoever. no equipment's ground lifted via cheaters.
Noticeable difference from when I didn't have dedicated lines.
Being an Electrical Engineer, I know that AC is AC and DC is DC and every piece of equipment I use converts the AC to DC internally. Therefore, phase absolutely does not matter and my system's sound is wonderful.
If you are going to put all your equipment on the same phase at the panel, try to make sure your house loads are balanced at the panel.
enjoy