The beauty of a ringing sound (5)
I believe the answer is:
belle
'the beauty' is the definition.
(I've seen this before)
'a ringing sound' is the wordplay.
'a ringing' becomes 'bell' (bell ringing is a kind of ringing).
'sound' indicates a 'sounds like' (homophone) clue.
'bell' sounds like 'BELLE'.
'of' acts as a link.
(Other definitions for belle that I've seen before include "-- Epoque, before the Great War" , "Girl who's fetching" , "Attractive woman" , "Beautiful female" , "Most attractive girl" .)