Need ears free for piece of music (8)
I believe the answer is:
serenade
'piece of music' is the definition.
(serenade is a kind of piece of music)
'need ears free' is the wordplay.
'free' indicates anagramming the letters.
'need'+'ears'='needears'
'needears' is an anagram of 'SERENADE'.
'for' acts as a link.
(Other definitions for serenade that I've seen before include "Music played by lover" , "Song to a lover" , "It's played or sung at a lover's window" , "Evening music (played outside woman's house)" , "Evening love song" .)