Sound of country music writer (7)
I believe the answer is:
britten
'music writer' is the definition.
'sound of country' is the wordplay.
'sound of' indicates a 'sounds like' (homophone) clue.
'country' becomes 'britain' (Britain is an example).
'britain' is a homophone of 'BRITTEN'.
(Other definitions for britten that I've seen before include "Composer born 1913" , "Composer of Peter Grimes" , "See 8" , "Billy Budd composer" , "British composer associated with Aldeburgh" .)