Artist supports innovative musical representations (9)
I believe the answer is:
simulacra
'representations' is the definition.
(simulacrum is a kind of representation)
'artist supports innovative musical' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'supports' says to put letters next to each other (bottom letters provide a support for the top ones).
'innovative' is an anagram indicator.
'musical' is an anagram of 'simulac'.
'ra' after 'simulac' is 'SIMULACRA'.
(Other definitions for simulacra that I've seen before include "Representations (of someone/something)" , "Images, representations" , "Representational images" , "Superficial impressions" , "Poor imitations" .)