a wire vibrating at what frequencies could be heard by the human ear?

Answer 1

The hearing range for a human is considered to be 20Hz to 20,000Hz. Many people do not hear the entire range and the sensitivity falls off at both ends. 2300hz is considered to be about the most sensitive point.

Answer 2

20Hz. to 18 kHz.
As you get older (>20) the high end attenuates. You are lucky if you can hear much above 4 kHz.
You might hear harmonics of infrasound and ultrasound; but they would have to be in that range.
20.6 Hz. is an octave below the low E1 on a bass guitar.
27.5 Hz. is the lowest note on a standard piano (A0).