Highlighted comments from the commenters below:
-123pailin:
Callas...the one and only!!! Releasing the beast in her. Is there one voice that ever had all that??? She was bigger than life, the Mount Everest that fell into the opera pond....So wonderful....
-From BZBlaner:
The early Nabucco is like the Vocal Olympics - endless fortissimo passages, treacherous octave drops, a sea of high notes. It's a voice ruiner for sure, but to think she added a high E-flat in "Deh perdona, deh perdona" at the end of the opera is just beyond belief. This is MONUMENTAL level singing, something we won't be hearing anytime soon.
-From Mister Opera
WOW! At 3:38 she sings D5, FORTE, in CHEST voice, like old castrati sang...Tosi, and Mancini in their books about singing say that sopranos had CHEST voice til D5 or even higher...
Callas is really OLD school (probably because of de Hidalgo)!!!

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