black music vs musical genre

black music and musical genre both are nouns.

Word	Noun	Adjective	Verb	Adverb
black music	Yes	No	No	No
musical genre	Yes	No	No	No

As nouns, musical genre is a hypernym of black music; that is, musical genre is a word with a broader meaning than black music:

black music: music created by African-American musicians; early forms were songs that had a melodic line and a strong rhythmic beat with repeated choruses
musical genre: an expressive style of music

Other hypernyms of black music include music genre, musical style.

black music (noun)	musical genre (noun)
music created by African-American musicians; early forms were songs that had a melodic line and a strong rhythmic beat with repeated choruses	an expressive style of music