PART HYMN' Part Hymn is a term used to describe a type of vocal music that is sung in four-part harmony. The four parts are Soprano, ALTO, Tenor, and Bass. ALTO is the second highest part and is usually sung by a female voice. It is characterized by its range, which is lower than the soprano and higher than the tenor. Part Hymn is often used in religious services and is a popular form of choral music.