Top 3 singers

clean vocals:
Kai Hansen (Gamma Ray)
Hansi Kürsch (Blind Guardian)
Tony Kakko (Sonata Arctica)

growls:
Katla (ex-Finntroll singer)
Angela Gossow (Arch Enemy)
Ville Seponpoika Sorvali (Moonsorrow)
 
Melodic Fan in the Area!!!!!!!!!!!:headbang::headbang::headbang::headbang:
Ralf Scheepers (ex Gammaray)
Michael Kiske (Helloween)
Thomas Rettke (Heavens Gate)
Andre Matos (Angra/Shaman)
Eric Adams (Manowar)

Otherwise...
Alexi Laiho (CoB)
Niklas Sundin (Dark Tranquility)
Anders Fridén (In Flames, in Clayman)
 
clean:
Mikael Åkerfeldt (Opeth)
Blaze Bayley (Blaze)
Mathias Blad (ex-Falconer)

growl/grim:
Mikael Åkerfeldt (Opeth, Bloodbath)
Alexi Laiho (Children of Bodom)
Mika Tönning (Catamenia)