Recover gold crowns by listening (7)
I believe the answer is:
aurally
'recover gold crowns by listening' is the definition.
I can't judge whether this definition defines the answer.
'recover gold' is the wordplay.
I cannot really understand how this works, but
'recover' could be 'rally' (rallying is a kind of recovering) and 'rally' is present in the answer.
'gold' could be 'au' (Au is the chemical symbol for gold) and 'au' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for aurally that I've seen before include "connected with hearing" , "Via the ear" , "How one may learn" .)