You might find it interesting to audition an MIT Oracle AC2 powercord with your Oppo. The improvement in sound will not be at all unremarkable. (I know the AC2 is expensive). I would be very interested to hear how much closer the sound is to your Esoteric on its regular power cord!
OPPO 105; how to beat it and at what price?
I am in the process of building my reference system around my new Wilson Alexia’s. I am currently using the OPPO 105. How much would I have to spend to get a significant audible improvement? What would that unit be?