For me it’s Neko Case in any of her bands.
For me, has always been Chris Cornell. Absolutely gutted when he died, knowing I’d never hear anything new from him again.
Adam Lambert.
Holy fuck his range and control. It’s insane.
Even if his music is mediocre, his vocals are amazing.
Pavarotti. Goosebumps. every. time.
Regina Spektor.
For my money no one can convey as much emotion through their voice as her.
Sara Bareilles
Is incredibly precise. Listening to her voice is like listening to what people are hoping for when they’re autotuning, but she nails it.
Ronnie James Dio.
Freddie Mercury!
He doesn’t sing too much these days
This one is not likely to be popular here, but I have to be totally honest and say: Miley Cyrus.
Don’t get me wrong. I am not really a fan of her or her music (nor am I a hater). But my god does that woman have an incredible voice and a mastery of how to use it.
Tetiana Shmailyuk from Jinjer - a Ukrainian metal band. Her ability to go from her growl to her clean vocals is absolutely wild to me.
Holy cow, that’s absolutely wild! There are a handful of female heavy metal vocalists I follow who do a similar things to this and the contrast between clear singing voices and their growls is just something special. Eg. Kasey Karlsen
Lzzy Hale has an incredible voice
Recently it’s this girl. https://youtu.be/YYoP9bxwg84
Her voice is out of this world. Sadly I don’t know how to write her name. [Symbol]OK
Her name is 王OK (thanks copy paste!). I like the first YouTube comment, which described her voice as ‘like a warm blanket during a cold winter morning’.
David Draiman lead vocalist of Disturbed
Not exactly what you’re asking for, but there’s this thing called “shape note singing.”
There’s a long story of why it exists, but people still do it, and even though it has roots in religion, and the songs are religious, the groups you find today never perform in a religious capacity.
Get a buddy and go to one of the meetings. Everybody sits in chairs, in a circle and everybody sings. No instruments, just voices.
It’s a beautiful, eerie sound which always falls flat in recordings.