Good question! Closest to the source then work backwards. I did this about 6 months ago, starting with some high priced WireWorld series 8 XLRs and speaker cables. I figured my power cord between 20 amp dedicated line and CorePower 1800 was plenty good (turns out not the case!). After reading several days of new posts to a AG thread titled Counterfeit Chinese Cables, I took the plunge buying just ONE coax cable to replace a Pangea Premier XE (MSRP was $169) with a Nordost Odin 2 knockoff. The downside 3+ weeks of high anticipation, however, it is amazing, so I then replaced the WW XLR between my Audio Alchemy DDP-1: Ditto, then Odin 2s replaced the WW speaker cables: Flabbergasted. I then upgraded all the PCs. First I tried Odin 2s but saw they also sold Odin 2 Gold- better still (YMMV), but I needed a heavier gauge for the wall to CorePower and CorePower to amp. Here a fellow ’phile directed me to Amazon for uber cheap PCs: Audiophile 10 AWG HiFi Power Cable 125V 15A Single Crystal Copper US AC Main Supply Cord Rhodium Plated NEMA 5-15P Plug IEC320-C15 C13 Connector for Speaker Subwoofer Turntable Amplifier 😍 He prefers the copper only. Regardless they blew away ~ 10 year old boutique PCs @ $500
I forgot to mention, I treated all new cables with MadScientist Graphene Cable Enhancer, so at the very least do that to what you have now
hth