Make sure that the presence of a conservatory (Oberlin) or music school (UCLA) on campus doesn’t have more cons than pros. Sometimes, in that case, the best teachers and performance opportunities go to the BM students in performance programs. (Ditto Eastman). Each school is a little different so you may have to probe deeply.
He can major in music and minor in or study other subjects. He can major in another area and continue music through classes, lesssons and performing. He can do a double degree. He can do a double major.
Tufts is a good suggestion- nice music department and strong in the other areas he is interested in,