Article written about musical performance (7)
I believe the answer is:
recital
'musical performance' is the definition.
(I've seen this before)
'article written about' is the wordplay.
'written about' is an anagram indicator (letters moved about before being rewritten).
'article' with letters rearranged gives 'RECITAL'.
(Other definitions for recital that I've seen before include "Article about musical entertainment" , "Performance of music by soloist" , "gig" , "Chamber music concert" , "Soloist's performance" .)