Sigrid Onegin in Mozart's Exultate Jubilate (Aleluja)

I used to think 3 octave voices had to be uneven by default with chesty low, weak middle and squally high notes...until I heard Onegin. She was a rare coloratura contralto who had a seamless, beautiful voice from top to bottom.
To be born with a multi octave voice is one thing but to master it and unify all your registers into one even voice is art.