Probably the best vocals I have ever heard was from Eddie Vedder.
Pearl Jam live playing "Black". MTV unplugged.
The Vocal Tone, Intimacy, Element, Authentic, Breath Control, it just goes on, it's just faultless vocals and a true real singer in my opinion.
Just because someone can sing a song and in key that's just called a good singer or a great singer even. Yet there is so much more to it. And I don't even know that much about singing. But each to there own it's just my choice for best vocal, or one of them because there are many others also who can rip some vocals. Each to there day or whatever. Everyone has there off days.