On the physical layer, yup pretty simple. I think the error checking and all that probably happens at a higher level. I didn’t go through the SD protocol but I thought I saw something involving error checking before.
At least some SD cards show you its block diagram and the better ones out there (Micron, Sandisk, Samsung, Greenliant etc.) pretty much have some form of ECC implemented.
True they show ECC. I'll dig in if I feel like it Hopefully the listening result comes quicker.