What type of copper is best for power cable?


I am planning to make a few power cord for myself to see if it will make any difference to the sound. Connectors will come from Marinco, but as for wire, I am not sure I should be using solid copper or stranded copper.
It seems like all my apartment internal wiring is using solid copper.
Any suggestion will be helpful.
andy2
Can you still get Marinco connectors? I thought Wattgate bought the exclusive rights to Marinco- I could be mistaken, just what I've heard.
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I haven't tried buying Marinco connectors yet. There is a local representative I can call on Monday. Will see then.
The odd things is I've been going all over town to find a decent female plug but can't seem to find any store that carry them. The only thing they have is the male plugs.