melomaniac
One with an abnormal fondness of music; a person who loves music.
He then amused himself with the fiddle—tried the French horn for a season, varying the matter by a few lessons upon the clarionet and hautboy, and finally improving his powers of endurance by a little practising of the Kent bugle. He at length became a perfect melomaniac, and was always in danger of being indicted as a nuisance by his less scientific neighbours, whose ears were doomed to suffer both by night and by day.
Where it comes from
From melo- (prefix meaning “music”) (from Ancient Greek μέλος (mélos, “song; melody, tune”)) + -maniac (from French maniaque, from Late Latin maniacus, from Ancient Greek μανιακός (maniakós), an adjectival form of μανία (manía, “madness; mad desire, compulsion”), ultimately from Proto-Indo-European *men- (“to think”)).
Adapted from the Wiktionary entry melomaniac (CC BY-SA 4.0).