Suggestions for Giant Killer rca coax digital cable under $500 used

I have used Pine Tree Audio for 4 years. These are good workmanship and neutral. However, am experimenting with some different cables.

For interconnects and digital what is the difference in sound, in general.

Sold OCC copper

Copper with silver plating

Pure silver.

I also thought Rhodium coated RCA with carbon ends. There are also silver and goal plated RCA connectors. These are all Chinese.  I got started after a dealer showed me a Audioquest Carbon(silver coated copper) which he was out of.  So far, I have a Chinese silver coated copper.  So far, it sounds pretty good for $13. It was funny different sellers use the same pictures, same prices, same descriptions.

Kimber D60 reviewer reference digital cable, Marigo apparition digital cable Jonathan Scull favorite. I have both as well.

1's and 0's. It doesn't matter.

charyro, new dac would be nice but would like to try a cable first.

Does spdif not have as big of an if impact as your typical interconnect?
 

What do most people use USB or balanced or other? I listen to mostly records so not even sure if spdif is way to go.

I was just hoping a better cable would give more information retrieval without being a tone control. Not looking to change voice of my system.

I just thought technology in digital cables had progressed in the 20 plus years over my JPS. JPS is all I’ve ever owned, I did try a friends $200 usb.