A serious comment: I have used both a very cheap interconnect with my CD player, and a moderately decent interconnect that I picked up used (not expensive). There clearly is a difference.
I suspect it is like everything else, law of diminishing returns. $10 > $75 fairly certain there would be a real difference. $150 > $2,376.06, not so much.
If I had $2,376.06 to spend, it would surely not be on cables... could get a number of good sample libraries, etc., etc., for that sort of money; not "snake oil".
What can be of use though are good used audiophile speakers, that are sometimes as flat as monitors. For general listening, some of the lower end audiophile speakers cost about the same as the "good" consumer grade speakers, and the quality difference is quite real.
Some of the audiophile companies also make monitors as well (if I could afford them, which I cannot, PMC would be high on the list, B&W as well).
One potential online source for the good used stuff is Audiogon.
And <smile> regarding the "wife notch" filter.