The thing about recs is that you, the student, are not allowed to see them. (At least you aren’t supposed to see them, not sure how they are submitted from internationals, though.) So teacher A writes a great rec, teacher B writes a good rec. Teacher C writes a generic rec and isn’t as good writer and ends up ruining the previous two recs because he/she inadvertently gives a back-handed compliment, such as “Johnny tries really hard and gets good grades, despite the fact that other students seem to struggle far less than he does.” Oops. And music teacher hasn’t got a clue, because he/she quite likely has never written a college rec for an American university. Meanwhile, your teachers/music teacher all send their recs merrily on their way to Harvard. You might end up with two dud recs that will not help you. I seriously would consider only asking teachers who have written these kind of recs before. Less is more, my friend.