The first video comes courtesy of the great British contralto Dame Clara Butt. The song is The Enchantress, by J. Hatton, and in it she hits a wonderful E3 at 0:52.
In this excerpt from the "Vivaldi's Women - Gloria" DVD, Margaret Jackson-Roberts sings the bass role in the "Gloria Patri" from Vivaldi's Dixit Dominus, in which she sings multpile A2's. A nice long-held A2 comes at 1:23. Margaret states that she can sing "down to F below the [bass] stave ... and ... down to C below the [bass] stave on a good day." Wow! Go Margaret!