- Female voices are generally considered to be more pleasant to listen to than male voices.
- Female vocalists are more popular in popular music than male vocalists.
Reason 2: Technical reasons
- Female voices are generally higher in pitch than male voices, making them easier to synthesize.
- There is a larger pool of professional female voice actresses available.
Reason 3: Historical reasons
- The first Vocaloid was a female character, named Hatsune Miku. This set a precedent for other Vocaloids to be female as well.