Meinrad
Fear the Engineer
I find there are more elements to outstanding vocals than just a good range - the vocalist has to speak out about his ideas in a way which will make people think about them as they should be thought about. He must know when to growl, when to sing clean, when to max out, and respond to the instrumental music. Another big element is how unique his vocals are - If he sounds just like most of the typical vocalists out there, who's going to pay any attention to the ideas he tries to convey?
One of my favorite vocalists is Serdj from Digimortal.
Not only does he convey his ideas well by switching from growls to clean vocals with timing that will inflict fear and wonder in listeners at the same time, he has very interesting ideas to begin with, and when he helps to write the instrumental music he is good at making it complete his vocals.
Maynard James Keenan from Tool, A Perfect Circle, and Puscifer is another awesome vocalist.
He has a very unique voice that no one else can imitate adequately, even those (like Adam Monroe) who can keep up with his complicated patterns, timing, and ability to use a different style for each of the different bands he works in.
Another vocalist I find particularly talented is Burton C. Bell from Fear Factory and City of Fire.
As Fear Factory has progressed, Burton has been less capable with range, but he's still unique and quite good at pounding his ideas into the minds of the listeners.
Alex Møklebust from Zeromancer is worth mentioning - his range is unremarkable, but he is very unique and good at his own little style.
One of my favorite vocalists is Serdj from Digimortal.
Not only does he convey his ideas well by switching from growls to clean vocals with timing that will inflict fear and wonder in listeners at the same time, he has very interesting ideas to begin with, and when he helps to write the instrumental music he is good at making it complete his vocals.
Maynard James Keenan from Tool, A Perfect Circle, and Puscifer is another awesome vocalist.
He has a very unique voice that no one else can imitate adequately, even those (like Adam Monroe) who can keep up with his complicated patterns, timing, and ability to use a different style for each of the different bands he works in.
Another vocalist I find particularly talented is Burton C. Bell from Fear Factory and City of Fire.
As Fear Factory has progressed, Burton has been less capable with range, but he's still unique and quite good at pounding his ideas into the minds of the listeners.
Alex Møklebust from Zeromancer is worth mentioning - his range is unremarkable, but he is very unique and good at his own little style.
Him and fellow Bloodbath alternate Mikael Åkerfeldt just fuse the brutal with the sinister (the element most extreme metal vocalists lack, IMHO) so well, not to mention both guys have super flexible clean vocals that put most to shame. 
