I wanted to go from a 2m pair to 1m, of the same kind. When I did, the left side was just a little low. Probably less than 2 dB. I replaced them with a pair of WW Eclipse 7 Gold I wasn’t using which were the right length. I had gotten frustrated with the huge connector sizes in a previous cabinet, which led me to DIY a lot of my cables..
Anyway, the WW 7 fixed the problem, I clearly have a fault in the DIY cables.
My point is, honestly based on buyers I have seen at stores sellers convince to spend $2k on a power cord, 95% of them would never have noticed this
So let me get this straight. You built a DIY so bad the left doesn't even sound like the right. Then you "fixed the problem" with a cable you paid a lot more for. And THAT convinced you that 95% of expensive cable buyers can't hear?
http://i.imgur.com/Z9F4SCr.jpg