I did not comment on selection of the Porter Ports - they are cryod Hubbell hospital outlets. Let’s let lincnabby burn them in first. The Hubbell outlets are brass and in my experience, brass elements tend to be on the sterile side and have a little bit of shouty effect in the highs.
Not from my experience. Of course it may depend on the audio equipment the receptacle is feeding.
From my experience the Hubbell Extra Heavy Duty Industrial Series HBL5262 (15 amp) and 5362 (20 amp) duplex receptacle is slightly on the warm side of neutral.
http://www.hubbell-wiring.com/press/catalog/a.pdf
See page A-12
As for the Hubbell duplex receptacle Albert Porter uses for his Porter Port, I remember reading in the past, he pays Hubbell to mix parts of hospital grade and HBL5262/5362 Extra Heavy Duty to build his outlets. I am not sure if he continued the practice or not. Special order can be expensive.
I have not been able to find an ad on Agon of Albert’s Porter Ports to check what the outlets are now.
Albert Porter’s old style cryo’d Porter Ports were the old stock Hubbell slim/Compact 8300H Hospital Grade 20 amp duplex receptacle. Back strap is non plated brass as well as the contacts, non plated brass. The sound was pretty much neutral. Hubbell no longer makes the 8200H/8300H hospital grade duplex receptacle in non plated contact and back strap.
Example of the old stock slim/Compact HBL8300H Hospital Grade duplex receptacle:
http://www.jzsupplies.com/lot-of-2-hubbell-hbl8300h-i5029065/
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Here is another older, I believe, Hubbell catalog.
http://www.hubbellcatalog.com/wiring/catalogpages/H5254.pdf
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