Bad art's seldom produced by great painters (3,7)
I believe the answer is:
old masters
'great painters' is the definition.
'old masters' can be an answer for 'painters' (old master is a kind of painter). I am not certain of the 'great' bit.
'bad art's seldom produced by' is the wordplay.
'bad' indicates anagramming the letters.
'produced by' is a charade indicator (letters next to each other).
'arts'+'seldom'='artsseldom'
'artsseldom' with letters rearranged gives 'OLD MASTERS'.
Can you help me to learn more?
(Other definitions for old masters that I've seen before include "Great Renaissance paintings" , "Classic artists" , "Great historic artists" , "Great works" , "Art's models (anag) - classic painters" .)