music vs bell ringing

music and bell ringing both are nouns.

Word	Noun	Adjective	Verb	Adverb
music	Yes	No	No	No
bell ringing	Yes	No	No	No

As nouns, bell ringing is a hyponym of music; that is, bell ringing is a word with a more specific, narrower meaning than music:

music (noun)	bell ringing (noun)
musical activity (singing or whistling etc.)	playing a set of bells that are (usually) hung in a tower
punishment for one's actions	persuasion of voters in a political campaign
any agreeable (pleasing and harmonious) sounds	the sound of someone playing a set of bells
(music) the sounds produced by singers or musical instruments (or reproductions of such sounds)
an artistic form of auditory communication incorporating instrumental or vocal tones in a structured and continuous manner