According to the author of 1 Chronicles, this verse is about the people from the family of Merari, who were helpers in the temple, standing on the left side. Ethan, a person in this family, is named along with his relatives.
1 Chronicles 6:44: And their brethren the sons of Merari [stood] on the left hand: Ethan the son of Kishi, the son of Abdi, the son of Malluch, [Kishi: or, Kushaiah]
1 Chronicles 6:33 lists Heman as the chief, contrary to the positions outlined in 1 Chronicles 6:44.
1 Chronicles 6:33: And these [are] they that waited with their children. Of the sons of the Kohathites: Heman a singer, the son of Joel, the son of Shemuel, [waited: Heb. stood]