The gifts will endow chairs at the Manhattan School of Music and at the University of Southern California's Thornton School of Music.
Alfred Mann is an entrepreneur who founded the aerospace company Spectrolab in 1956. He is also involved with companies in the fields of pharmaceuticals, electronic circuitry and biomedical research.
According to Forbes magazine, he is the 204th richest man in America.
Robert Mann is also a composer and conductor and has served as mentor to young musicians.