Article not about a novice lacking harmony (6)
I believe the answer is:
atonal
'article not about a novice lacking harmony' is the definition.
I can't judge whether this defines the answer.
'article not about a novice' is the wordplay.
'article' becomes 'a' (the indefinite article in English).
'about' is a reversal indicator.
'novice' becomes 'L' (as in a learner driver with L-plates on their car).
'not' reversed gives 'ton'.
'a'+'ton'+'a'+'l'='ATONAL'
Can you help me to learn more?
(Other definitions for atonal that I've seen before include "Musically, having no established key" , "(Of music) not in any key or mode" , "Keyless" , "(Of music) lacking key" , "Describes music not written in a particular key" .)