Thanks so much guys. It't not a C7. I took the three prong off of the computer and it does work , so it looks like that is it. On closer examination, one side is marked N and the other is L, so the plug is polarized with proper polarity directed by the asymmetry resulting from the bevels.
Power cable for Sony SCD-XA5400ES
Anybody know what the strange two prong non-polarized plug is at the back of the unit? The stock power cable is a joke and I would like to get something a bit more substantial but I can't identify what the female end is. It looks like the sort of plug common to computers but it's two prong instead of three. The male end is a regular polarized two prong plug.