He composed some enjoyable harmonies (5)
I believe the answer is:
lehar
'he composed' is the definition.
The definition suggests a singular noun which matches the answer.
'some enjoyable harmonies' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'LEHAR' is hidden within 'enjoyable harmonies'.
Can you help me to learn more?
(Other definitions for lehar that I've seen before include "Austrian of note" , "Viennese composer" , "Hungarian composer of operettas" , "Operettist" , "Franz . . . . . composed 'The Merry Widow'" .)