Sonority in a sentence as a noun

It's called the major system and it's based off the sonority rather than the spelling.

Romantic composers had been exploring sonority and dissonance for decades by the time Debussy came onto the scene.

I don't speak French well enough to do it in the original, so I'll have to try in translation:"And even if one wished to keep sonority on the side of the sensible and contingent signifier which would be strictly speaking impossible, since formal identities isolated within a sensible mass are already idealities that are not purely sensible, it would have to be admitted that the immediate and privileged unity which founds significance and the acts of language is the articulated unity of sound and sense within the phonic.

Sonority definitions

noun

having the character of a loud deep sound; the quality of being resonant

See also: plangency resonance reverberance ringing sonorousness vibrancy