Amp and preamp on same outlet?

If you wanted to set up the preamp and amp in an optimal manner you would have them on separate circuits. You would also have your digital on a separate circuit. The OP is not in a situation where he can do that.

Audiolover718, glad it has worked out well for you. Your punishment has been reduced to publicly wearing a sign stating "I have my amp and preamp on the same circuit."

Your punishment has been reduced to publicly wearing a sign stating "I have my amp and preamp on the same circuit."
Onhwy61

I have my preamp and amp plugged into the same 20 amp dedicated branch circuit and the digital on another. Works great for me. To maintain a constant voltage at the receptacle feeding the amp and preamp I chose to use 10-2 W/Grd NM-B cable branch circuit wiring.

As for my responses to this thread, I was trying to justify the reasoning behind the supposedly statement made by ARC in the owner’s manual the OP referred to.

In the case of the OP all that matters is his system sounds good to his ears plugged into a 120V 20 amp convenience outlet branch circuit. He does not have the luxury of finding out if just a new single 20 amp dedicated branch circuit would make a difference in the SQ sound of his system, let alone two.
Jim

A well regarded equipment manufacturer told me having everything on the same line is optimum. I suspect this is related to the ground loop considerations Al posted. Also, this is based on the assumption the one line is a dedicated circuit, as posted by Lowrider57. I have two 20-amp dedicated lines but currently use only one of them into an Isoclean filter, and the system sounds great.
If I add the fuse values of my two amps, preamp, DAC, and linear supply for my computer, together, my system can only draw a total of 15 amps so, from a power supply standpoint, I do not need the second line. Although, I have considered upgrading the breaker to 30 amps.
I have read about some new grounding devices coming to market that are said to make significant improvements in some systems.

Unless you have issues with too much current draw, just plug 'em in together enjoy and don't worry about it.

If it were a problem for me with my gear, I'd probably just buy different gear that works better together and be done.

If you have noise issues doing it the simple way, then you have a problem somewhere else and better to address that appropriately.

Or if you have a second outlet on a different circuit try that as an option. If it sounds better to you then keep it there otherwise it doesn't really matter.