harmonist

1a :  a member of a school of theorists in ancient Greece who intensively investigated the mathematical basis for musical pitch relations b archaic :  a person who composes or performs music c :  a composer who emphasizes harmony above other musical elements d :  a musician skilled in performing or improvising harmony e :  a collection of songs or hymns a religious songbook titled The Devotional Harmonist

2 :  one who shows the agreement or harmony of corresponding passages of different literary works (as the Gospels) editorial harmonists of the Pentateuch — Interpreter's Bible

3 :  harmonizer

4 usually capitalized [Harmony, community in Pennsylvania + English -ist] :  harmonite