An interesting side note:
An ASR thread involved a guy swearing that his Studio 530 sounds different when he plugged in through the HF binding posts rather than the LF posts... He admitted to trying different setups including
bi-something-ing them... and somehow decided that they sound "more present" plugged in through the HF...
Anyway, many have questioned his approach as you would expect.
I brought up the fact that it is likely that something was not seated or tightened properly when he started, which got rectified in his fooling around.
I was reminded of Gene testing his Kimber Cables with locking Bananas and also testing what happens when the bananas are loose. He very clearly demonstrated how the signal went from strong and clean to irregular.
At the same time, I found a nightlight we have that wasn't working properly and I gave it a little bump only to see it light up again. I pulled it out with virtually no resistance and plugged it back into the other outlet of that pair and it works fine.
Moral of the story is that Power Outlets (or ANY electrical connection) do matter insofar as the contact between conductors is strong and tight. A loose connection will suffer from poor performance. Household outlets can and will fail over time, especially with repeated use.
I would add that if OP's original lines were already taxed and perhaps had a failing wall outlet, he would quite possibly notice a problem in the performance of his Amp.
It is possible that the outlet or the line would be at fault. By changing to a dedicated line and new outlets, he now has as clean a pathway as his household electrical network can possibly provide.
Just thoughts as I wait for my morning Espressos (Espressi?) to fully engage.
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