So as a kid I used to watch Bob Ross all the time. I loved the way he spoke and it happen to air right around the time I got home from summer camp. I never knew why his voice was so soothing for me, but it was.
It seems now we have an actual term for it: "ASMR." I'm too lazy to Google whether this has been a term for a while, but I suppose that explains why his voice and paintings have relaxed me. I know it's very trendy right now with all the YouTubers trying to hitch on the hype. For a while I scoffed at those who seem to just monetize on the idea. But here I am, studying for finals, and I have ASMR videos playing in the background; I find it very helpful to stay focused. Much more than gentle music.
A few years ago I stumbled on GentleWhispering's channel before ASMR blew up, and that's usually the only channel I can tolerate. I don't understand those Tubers who put just weird sounds and whatnot; I'd rather have a soft voice saying actual sentences.
Also, is white noise included in this category? When my oldest was a baby we looked into ways to help her sleep. We got a white noise machine, and it worked so well that we realized we were falling asleep much better with it too, so we got one for our own room. We can't sleep without it now.