One's fach is about more than just how high one can sing, it's about tessitura and timbre. In opera most mezzo sopranos can sing up to C6 or so, but they're still considered mezzos because they are more comfortable with lower notes, and they have a darker, heavier voice.
It also depends on one's passagio: typically the soprano break into upper register lies around F5 or so, whereas an alto or mezzo has a lower one.
Jimmy, what are you doing here in the middle of the night? It's almost 9 PM!
Updated On: 1/6/07 at 01:58 PM