Mayer Joel Mandelbaum (born October 12, 1932) is an American music composer and teacher, best known for his use of microtonal tuning (notably just intonation and 19 equal temperament and the 31 equal temperament). He wrote the first Ph.D. dissertation on microtonality in 1961. He is married to stained glass artist Ellen Mandelbaum, and is the nephew of Abraham Edel.