plangency vs sonority

plangency and sonority both are nouns.

Word	Noun	Adjective	Verb	Adverb
plangency	Yes	No	No	No
sonority	Yes	No	No	No

As nouns, plangency and sonority are synonyms defined as:

plangency and sonority: having the character of a loud deep sound; the quality of being resonant

Other synonyms of plangency include resonance, reverberance, ringing, sonorousness, vibrancy.

plangency (noun)	sonority (noun)
having the character of a loud deep sound; the quality of being resonant	having the character of a loud deep sound; the quality of being resonant