What does voice range Eb4 - Eb5 mean?

Eb4 -Eb5 refers to the vocal range of a singer. The first part, Eb4, indicates the lowest note that the singer can hit. The second part, Eb5, indicates the highest note that the singer can hit. In this case, the singer can hit notes from Eb4 to Eb5, which is a range of one octave and one semitone.