It appears in Win 10 some sounds are disabled by design. Although the "Play Windows Start Up Sound" box may be checked in the Sounds panel, it generally does not play on boot. I have noticed it play after a warm restart, however.

The "Exit Windows" sound, as well as "Logon Windows" "Logoff Windows" are not present in the Sounds panel, but may be enabled via a change in the registry. Even though I did that, and they now appear in the Sounds panel, they do not play.

I read where MS decided to "streamline" Windows and eliminate sounds they feel are not important, thus the inability to use them. It would be nice if an option is presented to enable; I have preferred to use the Start Windows just as an audible notation that the system is coming on line if I am away from the desk during boot. "Start Windows" isn't a fully "the system is ready" though, I was going to test "Logon Windows" to see if a sound at that point is a better indication of the system truly being ready, but that is at present an unusable sound.

Anyone with other info is welcome to add constructive comments.