Audiophile Grade Wall Receptacle

Well failed tweeks of other types should have no bearing on how you approach AC outlets. I cant comment on Fukuda-sans take on different plating, but I will say that I have always favored copper on copper. Like metals so on. 

I think that the real advantage of better plating may be in the smoothness and lack of pits in the metal itself which would be accomplished by polishing. The grip of the socket as well and the material with which the socket is made. The influence of vibration and resonance on electrical items is well known.  

I wouldnt expect you to hear a difference as it appears you already know what the results of your test will be. Oh and just replacing your stock outlet with a Hubbell I dont think will give you much of an improvement. Going from a stock outlet to a Furutech, Oyaide or Cruze First might. Now if you hear a difference or not comes down to many things not even remotely related to basics like hearing acuity and predisposition. 

@boxcarman. , OP

I was surprised at the improvement when I put Shunyata SR-Z1 outlets in to replace the standard home wall outlets. Clearer and fuller sound. Maybe because they grip better or use better materials, but either way I'm happy with them. 

My gut feeling is no one would be able to hear the difference between a $3 standard house outlet and a $300 audiophile plug.  Just saying......"bigtwin"

If you had read my 1st post you would have learned that I heard a difference when testing 4 different plugs from a low of $25 to a middle price of $150 , aural memory is short so to test 4 outlets they were placed in a 4 gang box , so after the amp was warmed up for 1/2 hour i would play a song , turn the amp off and plug into another outlet and repeat after testing all 4 outlets I tried a different song and repeated , this was done along with a professional guitar player whose hearing is way better than mine and we both could hear differences . 

We both use AudioQuest , that's not to say that Furutech or Oyaide aren't better but we weren't out ot test outlets , we just used what we had around , the PS Audio now sends Ac to my TV .

A firm contact is important but the purity of the copper , the platings also make a difference , one you can hear . 

@vair68robert ​@audition__audio   What I'm asking for is some hard science to explain how an outlet, placed before the power conditioner, phono preamp, preamp, amp and speaker can have any impact on the sound.  All of the equipment has filters to scrub out noise and interference.  I'm not aware that electricity has a tonal component?  The idea that gold plating vs rodium plating could actually change the sound coming from a speaker is just a little hard for me to wrap my mind around.  And it's not that I have already made up my mind and therefore would not hear the difference, as audition_audio suggests, since the improvment will be so undeniable that I would not be able to miss it?  

I never said that you werent going to be able to miss the sonic difference and it is this type of sarcasm that gives me pause. ! I dont know anything about your system nor your hearing ability so I cant comment. There is no hard science just a myriad of testimonials from people that claim they can hear a difference. The question to ask yourself is if you cant measure something does this eliminate the possibility that this something could exist? Remember that many on this forum have systems that cost more than a car and approach or exceede the cost of a house. To think that the level of fidelity is the same, regardless of price, is ridiculous.