Copies alternative musical artist (9)
I believe the answer is:
simulacra
'copies' is the definition.
(I've seen this before)
'alternative musical artist' is the wordplay.
'alternative' is an anagram indicator (an alternative ordering of the letters).
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'musical' anagrammed gives 'simulac'.
'simulac'+'ra'='SIMULACRA'
(Other definitions for simulacra that I've seen before include "Representational images" , "Images, representations" , "Superficial impressions" , "Copies" , "Poor imitations" .)