Instrument uncovered evil gold ring (6)
I believe the answer is:
violin
'instrument' is the definition.
(violin is a kind of instrument)
'uncovered evil gold ring' is the wordplay.
'uncovered' says to take the centre.
'gold ring' becomes 'olin' (I can't explain this - if you can you should believe this answer much more).
The central letters of 'evil' are 'vi'.
'vi'+'olin'='VIOLIN'
Can you help me to learn more?
(Other definitions for violin that I've seen before include "Nigel Kennedy instrument" , "Bowed instrument" , "A stringed musical instrument, say a Stradivarius" , "It'a played with a bow" , "Menuhin's instrument" .)