What DOES the fox say?

It's an important question - and one that, for the most part, biologists can actually answer. There are a good number of posts on this topic already, so instead of repeating links, videos and words it's best for me to point you to articles that have already been written.  If you also want to find a site with a bunch of fox sounds - they're out there, too.

What Sound Does a Fox Really Make? (Popular Science)
Call of the Fox: What Sounds Does a Red Fox Make? (Decoded Science)

Remember there are different kinds of foxes, each potentially making their own calls, but I'm sure by now you're thinking, "Ok Mr. Early.* Way to take the fun out of it. Now can I just enjoy the song?"

Yes...yes you may.

*Personally, I was really hoping "The Fox" video would be something more like this