Power cord upgrade

Other people's advice on cables is useless.

Find a dealer (brick & mortar or online) who lets you audition them in your system, make sure they're broken in and try them in your system.

Trust your ears.  That's all that matters.

I've tried cables that sound terrible in other people's systems and not bad in mine.  And vice versa.

I used to think components were more important cables.

I now have done a 180 and am sure that cables are more important than components.

 Have a modest system compared with most of my friends in our audio club.  Many of them have spent well north of $500k on their rigs.

 Have now rotated many sets of high end power cables, interconnects and speaker cables through my sub $50k system and I can tell you without reservation that a set of $100k cables makes my system sound better than the best $750k rig I have heard.