Anyone hear of

Tried their $250 OCC copper interconnect cables. Sound was okay but fine details and air were reduced over my cheaper Belkin.

I use their silver AES/EBU.  https://audiosensibility.com/blog/products-2/digital-cables-occ-copper-and-occ-silver/#!/Signature-SE-Silver-AES-EBU-XLR-Digital-Cable/p/559064559

Excellent.

I use Audio Sensibility Statement Silver interconnects both RCA and XLR as appropriate, Statement speaker cables, and Statement power cords.  This for all components on two systems.  I first learned about this company and owner Steven Huang over a decade ago on the old VPI forum where both the man and his products enjoyed very high praise.  I called him and we spoke for a long time about my system, my goals and so forth. The outcome of that conversation was that he sent me a big box containing samples of connectors from across his entire range of offerings.  I spent perhaps a month switching back and forth comparing them all before settling on the Statement series as the best compromise for me.  I have had numerous occasions to compare with friends who brought over every other brand and at every price point.  I made the right choice for me.  Highly recommended.

I'm using several Audio Sensibility "Statement" power cables. They're OCC copper and terminated with gold Furutech connectors. They present a black background which enables so much smooth detail and microdynamics to be added to my music playback. I've never heard such a musical power cable before. I'll keep adding them to my system.

The bonus for me has been the weak Canadian dollar vs USD, it's like a discount on each purchase. But who knows how the global economy will be in the near future.