vibrancy vs plangency

vibrancy and plangency both are nouns.

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

As nouns, vibrancy and plangency are synonyms defined as:

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

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

vibrancy (noun)	plangency (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