galaxy s5 NOTIFICATION RINGTONE page. I want to add my own text notification sound. HOW?

[AC Question]

I want to use my own voice (and sounds) instead of the sound notification choices given. I am able to “add” my own under the ringtone selection, but not on the TEXT notification menu. Is there a way to do this? It doesn’t have an ” add” option. It only says cancel and OK. The Notification Sound menu also does not have the “add ” option. The “regular” ringtone page has an “add” option. Or is there another settings menu somewhere that will allow me to add my own text alert sounds?