Expert seen in some art broadcast (7)
I believe the answer is:
maestro
'expert' is the definition.
(I've seen this before)
'some art broadcast' is the wordplay.
'broadcast' indicates an anagram.
'some'+'art'='someart'
'someart' with letters rearranged gives 'MAESTRO'.
'seen in' is the link.
(Other definitions for maestro that I've seen before include "Distinguished artist" , "Highly talented figure in a given field" , "special performer" , "Some art (anag.)" , "Accomplished musician" .)