Outlets and Wire Gauge? - Please help!


I finally contracted an electrician to run two dedicated lines - a week from today! I have been reading thread after thread and the consensus appears to be going with 10awg wire for the 20amp run. My problem is two-fold:

  1. I'm stuck selecting an outlet because the electrician says that no 20amp outlet can take 10awg, that "10awg is for 30amp outlets".
  2. I'm stuck selecting an outlet because of what it might do to my sound. 

I simply want to install something good that's going to feed a Puritan Audio PSM156. I am now running ADG Gran Vivace monos. I prefer a rich midrange.

Additionally, I asked for both a 15 and 20 amp run. People suggested I do this so my sources can be run off the 15A with amps / subs off of the 20A, but someone here mentioned ground loops? I am not well-versed in things electrical. Ideally I would like to know if I should stick with the two runs, and what would be a few good choices for each outlet if I do. @jea48 @erik_squires ... I have seen solid advice from you on the topic of outlets, but they lack things specific to awg and outlet type.

Thank you in advance!

PS I estimate the length of the run to be approximately 50', max.

128x128izjjzi
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@jea48 I live in a split level ranch, so the panel is on the bottom floor in an unfinished room used as the laundry room. It is quite large. The adjacent room has the oil burner, two tanks and shelves of storage. The metal jacketed cables will be run through the floor joists and through a hole to be drilled through the concrete wall. The boiler room is under the garage and is concrete on all sides. My audio room is behind this room. 

Left side of the panel has seven free slots with only one left on the right (20 per side). A new solar panel system has a double breaker in the bottom two slots on the left side, so the free seven are directly above this one.

@raysmtb1 My last sentence is not a statement, it is a question. A question based on a great deal of reading and videos demonstrating how sound can change over time from an outlet. I have seen and heard too much in this realm to not discount claims that an outlet too will change the sound over time. 

Best, and happy listening!

@izjjzi sorry if I was being a little rough last night. I think I blew a gasket after reading so much bad information on the this forum. The only way that I know that an outlet can change over time is if a vermin chews through the wire feeding the outlet. Many of these threads end up leaning towards the science deniers because the people arguing for science tend to get their comments deleted. I think it’s probably because they can’t believe what they’re reading and lose their mind and maybe should’ve not used a derogatory word or two…either that or, the science crowd doesn’t have a way of putting money in the forum owners coffers, like all of the manufactures of this junk do. Please accept my apology.

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